star birth occurs in a nebula. a star's initial mass determines the star’s temperature,...
TRANSCRIPT
Star birth occurs in a nebula A stars initial mass determines the starrsquos temperature luminosity and diameter that ultimately
decides which life stages and type of death it will experience
The larger the star the shorter its life will be
Hydrostatic Equilibrium a star must be very hot and dense inside to balance its own GRAVITY
TEMPERATURE inside a star governs the rate of nuclear reactions WHICH determines its LUMINOSITY (energy radiated by astronomical object seen by us as light)
The balance between gravity pushing inward and outwardpressure is maintained by heat due to nuclear reactions andcompression is called HYDROSTATIC EQUILIBRIUM
SOhellipIf a star expands or contracts hydrostatic equilibrium Is not in place
NEBULA
bull Large clouds of gas and dust that contract due to gravitational force as it becomes hotter
1st Stage of Life
Protostar
hot condensed object of gas and dust that is pulled together by gravity at the center of a nebula
it generates energy and shines but is NOT hot enough to ignite nuclear fusion
Nuclear Fusion hydrogen atoms fuse into helium creating the intense energy found in stars
2nd Stage
bull Main Sequence (the Sun)ndashLongest stage stable starndashHydrogen changes into helium which
creates enormous amounts of energyndashThe size of the star does not change
muchndash90 of all stars
A Star of a Jokehellip
A woman at a gas station noticed a spaceship landing in front of her An alien stepped out of the spaceship and started to pump gas into it The woman noticed the letters UFO printed on the side of the ship She turned to the alien and asked Does UFO stand for Unidentified Flying Object
The alien answered No it stands for Unleaded Fuel Only
3rd stageGiants and Supergiants
ndash Main Sequence star becomes a red giant
bull Red giant star that expands 50x their normal size and cools (giving it a reddish color) it loses all its hydrogen appears brighter
bull Supergiant Large star with high
mass that become even hotter and expanding even more
It is 100rsquos of times hotter and more luminous than a red giant
Supernova
bull gigantic explosion in which a massive star collapses
ndash Occurs after a massive star uses up its fuel source
Supernova Remnant
White Dwarf
bull small hot star bull Fuel is used up
ndashFinal stage for some starsndashCan shine for billions of
years before they completely cool and extinguish
Black Dwarf
bull The remains of a white dwarf after it has completely cooledbull Scientists donot think universeis old enough tohave any black dwarfs yet
Neutron Star
A neutron star is a type of remnant that can result from the gravitational collapse of a massive star during a supernova event
Small dense star-one teaspoon would weigh a billion tons on Earth
What is a Black Hole
bull an object that is so massive that light cannot escape its gravity
Did you knowhellip
Astronomers can detect black holes by using X-ray telescopes
Pulsars
A neutron star that spins and sends out beams of radiation is called a pulsar
Hertzprung-Russell Diagram
Shows the relationship between a starrsquos surface temperature and absolute magnitude
ndash Used to study the lives of stars
ndash Most stars lie along the main sequence portion of the diagram
Our Place in Our Galaxy
Be careful about wishing on starshellip
Whatrsquos the Difference
Universe
Galaxy
Image credits NASA STScI
Solar System
Where is our Solar System
Visible stars gas dust in the Milky Way Galaxy
Image credits NASA STScI
Solar System
here
What Are Galaxies
bull A galaxy is a system of stars dust and gas held together by gravity
bull Galaxies are large collections of starshellip
millions and billions of stars
bull There are hundreds of billions of galaxies in the Universe
bull Millions to hundreds of billions of stars in each galaxy
Galaxy Factsbull The most distant galaxies ever photographed are as far as 10
billion to 13 billion light-years awaybull Large galaxies have more than a trillion stars bull Only three galaxies outside the Milky Way are visible with
the unaided eye People in the Northern Hemisphere can see the Andromeda Galaxy which is about 2 million light-years away People in the Southern Hemisphere can see the Large Magellanic Cloud which is about 160000 light-years from Earth and the Small Magellanic Cloud which is about 180000 light-years away
Rememberhellip
A light-year is the distance that light travels in a vacuum in a year -- about 588 trillion miles (946 trillion kilometers)
An astronomical unit is 93 million miles or 150 million km (average distance between Sun and the Earth)
The speed (velocity) of light is 300000 kmsec
1048708Galaxies are classified based on shape
1 Spiral--rotating disk (with arms) 2 Ellipticalmdashspheroid or oval disk of
stars with more chaotic motion3 Irregular--none of the above
Three Main Types of Galaxies
Elliptical Spiral Irregular
Examples of Three Main Galaxy Types
Looking at the Milky WayA Spiral Galaxy
Viewed as a bright band of stars across the sky
There are about 200-400 billion stars in the Milky Way
Much of the Milky Way is blocked by dust seen as a dark band through the middle of the Milky Way1048708
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
Hydrostatic Equilibrium a star must be very hot and dense inside to balance its own GRAVITY
TEMPERATURE inside a star governs the rate of nuclear reactions WHICH determines its LUMINOSITY (energy radiated by astronomical object seen by us as light)
The balance between gravity pushing inward and outwardpressure is maintained by heat due to nuclear reactions andcompression is called HYDROSTATIC EQUILIBRIUM
SOhellipIf a star expands or contracts hydrostatic equilibrium Is not in place
NEBULA
bull Large clouds of gas and dust that contract due to gravitational force as it becomes hotter
1st Stage of Life
Protostar
hot condensed object of gas and dust that is pulled together by gravity at the center of a nebula
it generates energy and shines but is NOT hot enough to ignite nuclear fusion
Nuclear Fusion hydrogen atoms fuse into helium creating the intense energy found in stars
2nd Stage
bull Main Sequence (the Sun)ndashLongest stage stable starndashHydrogen changes into helium which
creates enormous amounts of energyndashThe size of the star does not change
muchndash90 of all stars
A Star of a Jokehellip
A woman at a gas station noticed a spaceship landing in front of her An alien stepped out of the spaceship and started to pump gas into it The woman noticed the letters UFO printed on the side of the ship She turned to the alien and asked Does UFO stand for Unidentified Flying Object
The alien answered No it stands for Unleaded Fuel Only
3rd stageGiants and Supergiants
ndash Main Sequence star becomes a red giant
bull Red giant star that expands 50x their normal size and cools (giving it a reddish color) it loses all its hydrogen appears brighter
bull Supergiant Large star with high
mass that become even hotter and expanding even more
It is 100rsquos of times hotter and more luminous than a red giant
Supernova
bull gigantic explosion in which a massive star collapses
ndash Occurs after a massive star uses up its fuel source
Supernova Remnant
White Dwarf
bull small hot star bull Fuel is used up
ndashFinal stage for some starsndashCan shine for billions of
years before they completely cool and extinguish
Black Dwarf
bull The remains of a white dwarf after it has completely cooledbull Scientists donot think universeis old enough tohave any black dwarfs yet
Neutron Star
A neutron star is a type of remnant that can result from the gravitational collapse of a massive star during a supernova event
Small dense star-one teaspoon would weigh a billion tons on Earth
What is a Black Hole
bull an object that is so massive that light cannot escape its gravity
Did you knowhellip
Astronomers can detect black holes by using X-ray telescopes
Pulsars
A neutron star that spins and sends out beams of radiation is called a pulsar
Hertzprung-Russell Diagram
Shows the relationship between a starrsquos surface temperature and absolute magnitude
ndash Used to study the lives of stars
ndash Most stars lie along the main sequence portion of the diagram
Our Place in Our Galaxy
Be careful about wishing on starshellip
Whatrsquos the Difference
Universe
Galaxy
Image credits NASA STScI
Solar System
Where is our Solar System
Visible stars gas dust in the Milky Way Galaxy
Image credits NASA STScI
Solar System
here
What Are Galaxies
bull A galaxy is a system of stars dust and gas held together by gravity
bull Galaxies are large collections of starshellip
millions and billions of stars
bull There are hundreds of billions of galaxies in the Universe
bull Millions to hundreds of billions of stars in each galaxy
Galaxy Factsbull The most distant galaxies ever photographed are as far as 10
billion to 13 billion light-years awaybull Large galaxies have more than a trillion stars bull Only three galaxies outside the Milky Way are visible with
the unaided eye People in the Northern Hemisphere can see the Andromeda Galaxy which is about 2 million light-years away People in the Southern Hemisphere can see the Large Magellanic Cloud which is about 160000 light-years from Earth and the Small Magellanic Cloud which is about 180000 light-years away
Rememberhellip
A light-year is the distance that light travels in a vacuum in a year -- about 588 trillion miles (946 trillion kilometers)
An astronomical unit is 93 million miles or 150 million km (average distance between Sun and the Earth)
The speed (velocity) of light is 300000 kmsec
1048708Galaxies are classified based on shape
1 Spiral--rotating disk (with arms) 2 Ellipticalmdashspheroid or oval disk of
stars with more chaotic motion3 Irregular--none of the above
Three Main Types of Galaxies
Elliptical Spiral Irregular
Examples of Three Main Galaxy Types
Looking at the Milky WayA Spiral Galaxy
Viewed as a bright band of stars across the sky
There are about 200-400 billion stars in the Milky Way
Much of the Milky Way is blocked by dust seen as a dark band through the middle of the Milky Way1048708
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
NEBULA
bull Large clouds of gas and dust that contract due to gravitational force as it becomes hotter
1st Stage of Life
Protostar
hot condensed object of gas and dust that is pulled together by gravity at the center of a nebula
it generates energy and shines but is NOT hot enough to ignite nuclear fusion
Nuclear Fusion hydrogen atoms fuse into helium creating the intense energy found in stars
2nd Stage
bull Main Sequence (the Sun)ndashLongest stage stable starndashHydrogen changes into helium which
creates enormous amounts of energyndashThe size of the star does not change
muchndash90 of all stars
A Star of a Jokehellip
A woman at a gas station noticed a spaceship landing in front of her An alien stepped out of the spaceship and started to pump gas into it The woman noticed the letters UFO printed on the side of the ship She turned to the alien and asked Does UFO stand for Unidentified Flying Object
The alien answered No it stands for Unleaded Fuel Only
3rd stageGiants and Supergiants
ndash Main Sequence star becomes a red giant
bull Red giant star that expands 50x their normal size and cools (giving it a reddish color) it loses all its hydrogen appears brighter
bull Supergiant Large star with high
mass that become even hotter and expanding even more
It is 100rsquos of times hotter and more luminous than a red giant
Supernova
bull gigantic explosion in which a massive star collapses
ndash Occurs after a massive star uses up its fuel source
Supernova Remnant
White Dwarf
bull small hot star bull Fuel is used up
ndashFinal stage for some starsndashCan shine for billions of
years before they completely cool and extinguish
Black Dwarf
bull The remains of a white dwarf after it has completely cooledbull Scientists donot think universeis old enough tohave any black dwarfs yet
Neutron Star
A neutron star is a type of remnant that can result from the gravitational collapse of a massive star during a supernova event
Small dense star-one teaspoon would weigh a billion tons on Earth
What is a Black Hole
bull an object that is so massive that light cannot escape its gravity
Did you knowhellip
Astronomers can detect black holes by using X-ray telescopes
Pulsars
A neutron star that spins and sends out beams of radiation is called a pulsar
Hertzprung-Russell Diagram
Shows the relationship between a starrsquos surface temperature and absolute magnitude
ndash Used to study the lives of stars
ndash Most stars lie along the main sequence portion of the diagram
Our Place in Our Galaxy
Be careful about wishing on starshellip
Whatrsquos the Difference
Universe
Galaxy
Image credits NASA STScI
Solar System
Where is our Solar System
Visible stars gas dust in the Milky Way Galaxy
Image credits NASA STScI
Solar System
here
What Are Galaxies
bull A galaxy is a system of stars dust and gas held together by gravity
bull Galaxies are large collections of starshellip
millions and billions of stars
bull There are hundreds of billions of galaxies in the Universe
bull Millions to hundreds of billions of stars in each galaxy
Galaxy Factsbull The most distant galaxies ever photographed are as far as 10
billion to 13 billion light-years awaybull Large galaxies have more than a trillion stars bull Only three galaxies outside the Milky Way are visible with
the unaided eye People in the Northern Hemisphere can see the Andromeda Galaxy which is about 2 million light-years away People in the Southern Hemisphere can see the Large Magellanic Cloud which is about 160000 light-years from Earth and the Small Magellanic Cloud which is about 180000 light-years away
Rememberhellip
A light-year is the distance that light travels in a vacuum in a year -- about 588 trillion miles (946 trillion kilometers)
An astronomical unit is 93 million miles or 150 million km (average distance between Sun and the Earth)
The speed (velocity) of light is 300000 kmsec
1048708Galaxies are classified based on shape
1 Spiral--rotating disk (with arms) 2 Ellipticalmdashspheroid or oval disk of
stars with more chaotic motion3 Irregular--none of the above
Three Main Types of Galaxies
Elliptical Spiral Irregular
Examples of Three Main Galaxy Types
Looking at the Milky WayA Spiral Galaxy
Viewed as a bright band of stars across the sky
There are about 200-400 billion stars in the Milky Way
Much of the Milky Way is blocked by dust seen as a dark band through the middle of the Milky Way1048708
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
1st Stage of Life
Protostar
hot condensed object of gas and dust that is pulled together by gravity at the center of a nebula
it generates energy and shines but is NOT hot enough to ignite nuclear fusion
Nuclear Fusion hydrogen atoms fuse into helium creating the intense energy found in stars
2nd Stage
bull Main Sequence (the Sun)ndashLongest stage stable starndashHydrogen changes into helium which
creates enormous amounts of energyndashThe size of the star does not change
muchndash90 of all stars
A Star of a Jokehellip
A woman at a gas station noticed a spaceship landing in front of her An alien stepped out of the spaceship and started to pump gas into it The woman noticed the letters UFO printed on the side of the ship She turned to the alien and asked Does UFO stand for Unidentified Flying Object
The alien answered No it stands for Unleaded Fuel Only
3rd stageGiants and Supergiants
ndash Main Sequence star becomes a red giant
bull Red giant star that expands 50x their normal size and cools (giving it a reddish color) it loses all its hydrogen appears brighter
bull Supergiant Large star with high
mass that become even hotter and expanding even more
It is 100rsquos of times hotter and more luminous than a red giant
Supernova
bull gigantic explosion in which a massive star collapses
ndash Occurs after a massive star uses up its fuel source
Supernova Remnant
White Dwarf
bull small hot star bull Fuel is used up
ndashFinal stage for some starsndashCan shine for billions of
years before they completely cool and extinguish
Black Dwarf
bull The remains of a white dwarf after it has completely cooledbull Scientists donot think universeis old enough tohave any black dwarfs yet
Neutron Star
A neutron star is a type of remnant that can result from the gravitational collapse of a massive star during a supernova event
Small dense star-one teaspoon would weigh a billion tons on Earth
What is a Black Hole
bull an object that is so massive that light cannot escape its gravity
Did you knowhellip
Astronomers can detect black holes by using X-ray telescopes
Pulsars
A neutron star that spins and sends out beams of radiation is called a pulsar
Hertzprung-Russell Diagram
Shows the relationship between a starrsquos surface temperature and absolute magnitude
ndash Used to study the lives of stars
ndash Most stars lie along the main sequence portion of the diagram
Our Place in Our Galaxy
Be careful about wishing on starshellip
Whatrsquos the Difference
Universe
Galaxy
Image credits NASA STScI
Solar System
Where is our Solar System
Visible stars gas dust in the Milky Way Galaxy
Image credits NASA STScI
Solar System
here
What Are Galaxies
bull A galaxy is a system of stars dust and gas held together by gravity
bull Galaxies are large collections of starshellip
millions and billions of stars
bull There are hundreds of billions of galaxies in the Universe
bull Millions to hundreds of billions of stars in each galaxy
Galaxy Factsbull The most distant galaxies ever photographed are as far as 10
billion to 13 billion light-years awaybull Large galaxies have more than a trillion stars bull Only three galaxies outside the Milky Way are visible with
the unaided eye People in the Northern Hemisphere can see the Andromeda Galaxy which is about 2 million light-years away People in the Southern Hemisphere can see the Large Magellanic Cloud which is about 160000 light-years from Earth and the Small Magellanic Cloud which is about 180000 light-years away
Rememberhellip
A light-year is the distance that light travels in a vacuum in a year -- about 588 trillion miles (946 trillion kilometers)
An astronomical unit is 93 million miles or 150 million km (average distance between Sun and the Earth)
The speed (velocity) of light is 300000 kmsec
1048708Galaxies are classified based on shape
1 Spiral--rotating disk (with arms) 2 Ellipticalmdashspheroid or oval disk of
stars with more chaotic motion3 Irregular--none of the above
Three Main Types of Galaxies
Elliptical Spiral Irregular
Examples of Three Main Galaxy Types
Looking at the Milky WayA Spiral Galaxy
Viewed as a bright band of stars across the sky
There are about 200-400 billion stars in the Milky Way
Much of the Milky Way is blocked by dust seen as a dark band through the middle of the Milky Way1048708
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
2nd Stage
bull Main Sequence (the Sun)ndashLongest stage stable starndashHydrogen changes into helium which
creates enormous amounts of energyndashThe size of the star does not change
muchndash90 of all stars
A Star of a Jokehellip
A woman at a gas station noticed a spaceship landing in front of her An alien stepped out of the spaceship and started to pump gas into it The woman noticed the letters UFO printed on the side of the ship She turned to the alien and asked Does UFO stand for Unidentified Flying Object
The alien answered No it stands for Unleaded Fuel Only
3rd stageGiants and Supergiants
ndash Main Sequence star becomes a red giant
bull Red giant star that expands 50x their normal size and cools (giving it a reddish color) it loses all its hydrogen appears brighter
bull Supergiant Large star with high
mass that become even hotter and expanding even more
It is 100rsquos of times hotter and more luminous than a red giant
Supernova
bull gigantic explosion in which a massive star collapses
ndash Occurs after a massive star uses up its fuel source
Supernova Remnant
White Dwarf
bull small hot star bull Fuel is used up
ndashFinal stage for some starsndashCan shine for billions of
years before they completely cool and extinguish
Black Dwarf
bull The remains of a white dwarf after it has completely cooledbull Scientists donot think universeis old enough tohave any black dwarfs yet
Neutron Star
A neutron star is a type of remnant that can result from the gravitational collapse of a massive star during a supernova event
Small dense star-one teaspoon would weigh a billion tons on Earth
What is a Black Hole
bull an object that is so massive that light cannot escape its gravity
Did you knowhellip
Astronomers can detect black holes by using X-ray telescopes
Pulsars
A neutron star that spins and sends out beams of radiation is called a pulsar
Hertzprung-Russell Diagram
Shows the relationship between a starrsquos surface temperature and absolute magnitude
ndash Used to study the lives of stars
ndash Most stars lie along the main sequence portion of the diagram
Our Place in Our Galaxy
Be careful about wishing on starshellip
Whatrsquos the Difference
Universe
Galaxy
Image credits NASA STScI
Solar System
Where is our Solar System
Visible stars gas dust in the Milky Way Galaxy
Image credits NASA STScI
Solar System
here
What Are Galaxies
bull A galaxy is a system of stars dust and gas held together by gravity
bull Galaxies are large collections of starshellip
millions and billions of stars
bull There are hundreds of billions of galaxies in the Universe
bull Millions to hundreds of billions of stars in each galaxy
Galaxy Factsbull The most distant galaxies ever photographed are as far as 10
billion to 13 billion light-years awaybull Large galaxies have more than a trillion stars bull Only three galaxies outside the Milky Way are visible with
the unaided eye People in the Northern Hemisphere can see the Andromeda Galaxy which is about 2 million light-years away People in the Southern Hemisphere can see the Large Magellanic Cloud which is about 160000 light-years from Earth and the Small Magellanic Cloud which is about 180000 light-years away
Rememberhellip
A light-year is the distance that light travels in a vacuum in a year -- about 588 trillion miles (946 trillion kilometers)
An astronomical unit is 93 million miles or 150 million km (average distance between Sun and the Earth)
The speed (velocity) of light is 300000 kmsec
1048708Galaxies are classified based on shape
1 Spiral--rotating disk (with arms) 2 Ellipticalmdashspheroid or oval disk of
stars with more chaotic motion3 Irregular--none of the above
Three Main Types of Galaxies
Elliptical Spiral Irregular
Examples of Three Main Galaxy Types
Looking at the Milky WayA Spiral Galaxy
Viewed as a bright band of stars across the sky
There are about 200-400 billion stars in the Milky Way
Much of the Milky Way is blocked by dust seen as a dark band through the middle of the Milky Way1048708
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
A Star of a Jokehellip
A woman at a gas station noticed a spaceship landing in front of her An alien stepped out of the spaceship and started to pump gas into it The woman noticed the letters UFO printed on the side of the ship She turned to the alien and asked Does UFO stand for Unidentified Flying Object
The alien answered No it stands for Unleaded Fuel Only
3rd stageGiants and Supergiants
ndash Main Sequence star becomes a red giant
bull Red giant star that expands 50x their normal size and cools (giving it a reddish color) it loses all its hydrogen appears brighter
bull Supergiant Large star with high
mass that become even hotter and expanding even more
It is 100rsquos of times hotter and more luminous than a red giant
Supernova
bull gigantic explosion in which a massive star collapses
ndash Occurs after a massive star uses up its fuel source
Supernova Remnant
White Dwarf
bull small hot star bull Fuel is used up
ndashFinal stage for some starsndashCan shine for billions of
years before they completely cool and extinguish
Black Dwarf
bull The remains of a white dwarf after it has completely cooledbull Scientists donot think universeis old enough tohave any black dwarfs yet
Neutron Star
A neutron star is a type of remnant that can result from the gravitational collapse of a massive star during a supernova event
Small dense star-one teaspoon would weigh a billion tons on Earth
What is a Black Hole
bull an object that is so massive that light cannot escape its gravity
Did you knowhellip
Astronomers can detect black holes by using X-ray telescopes
Pulsars
A neutron star that spins and sends out beams of radiation is called a pulsar
Hertzprung-Russell Diagram
Shows the relationship between a starrsquos surface temperature and absolute magnitude
ndash Used to study the lives of stars
ndash Most stars lie along the main sequence portion of the diagram
Our Place in Our Galaxy
Be careful about wishing on starshellip
Whatrsquos the Difference
Universe
Galaxy
Image credits NASA STScI
Solar System
Where is our Solar System
Visible stars gas dust in the Milky Way Galaxy
Image credits NASA STScI
Solar System
here
What Are Galaxies
bull A galaxy is a system of stars dust and gas held together by gravity
bull Galaxies are large collections of starshellip
millions and billions of stars
bull There are hundreds of billions of galaxies in the Universe
bull Millions to hundreds of billions of stars in each galaxy
Galaxy Factsbull The most distant galaxies ever photographed are as far as 10
billion to 13 billion light-years awaybull Large galaxies have more than a trillion stars bull Only three galaxies outside the Milky Way are visible with
the unaided eye People in the Northern Hemisphere can see the Andromeda Galaxy which is about 2 million light-years away People in the Southern Hemisphere can see the Large Magellanic Cloud which is about 160000 light-years from Earth and the Small Magellanic Cloud which is about 180000 light-years away
Rememberhellip
A light-year is the distance that light travels in a vacuum in a year -- about 588 trillion miles (946 trillion kilometers)
An astronomical unit is 93 million miles or 150 million km (average distance between Sun and the Earth)
The speed (velocity) of light is 300000 kmsec
1048708Galaxies are classified based on shape
1 Spiral--rotating disk (with arms) 2 Ellipticalmdashspheroid or oval disk of
stars with more chaotic motion3 Irregular--none of the above
Three Main Types of Galaxies
Elliptical Spiral Irregular
Examples of Three Main Galaxy Types
Looking at the Milky WayA Spiral Galaxy
Viewed as a bright band of stars across the sky
There are about 200-400 billion stars in the Milky Way
Much of the Milky Way is blocked by dust seen as a dark band through the middle of the Milky Way1048708
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
3rd stageGiants and Supergiants
ndash Main Sequence star becomes a red giant
bull Red giant star that expands 50x their normal size and cools (giving it a reddish color) it loses all its hydrogen appears brighter
bull Supergiant Large star with high
mass that become even hotter and expanding even more
It is 100rsquos of times hotter and more luminous than a red giant
Supernova
bull gigantic explosion in which a massive star collapses
ndash Occurs after a massive star uses up its fuel source
Supernova Remnant
White Dwarf
bull small hot star bull Fuel is used up
ndashFinal stage for some starsndashCan shine for billions of
years before they completely cool and extinguish
Black Dwarf
bull The remains of a white dwarf after it has completely cooledbull Scientists donot think universeis old enough tohave any black dwarfs yet
Neutron Star
A neutron star is a type of remnant that can result from the gravitational collapse of a massive star during a supernova event
Small dense star-one teaspoon would weigh a billion tons on Earth
What is a Black Hole
bull an object that is so massive that light cannot escape its gravity
Did you knowhellip
Astronomers can detect black holes by using X-ray telescopes
Pulsars
A neutron star that spins and sends out beams of radiation is called a pulsar
Hertzprung-Russell Diagram
Shows the relationship between a starrsquos surface temperature and absolute magnitude
ndash Used to study the lives of stars
ndash Most stars lie along the main sequence portion of the diagram
Our Place in Our Galaxy
Be careful about wishing on starshellip
Whatrsquos the Difference
Universe
Galaxy
Image credits NASA STScI
Solar System
Where is our Solar System
Visible stars gas dust in the Milky Way Galaxy
Image credits NASA STScI
Solar System
here
What Are Galaxies
bull A galaxy is a system of stars dust and gas held together by gravity
bull Galaxies are large collections of starshellip
millions and billions of stars
bull There are hundreds of billions of galaxies in the Universe
bull Millions to hundreds of billions of stars in each galaxy
Galaxy Factsbull The most distant galaxies ever photographed are as far as 10
billion to 13 billion light-years awaybull Large galaxies have more than a trillion stars bull Only three galaxies outside the Milky Way are visible with
the unaided eye People in the Northern Hemisphere can see the Andromeda Galaxy which is about 2 million light-years away People in the Southern Hemisphere can see the Large Magellanic Cloud which is about 160000 light-years from Earth and the Small Magellanic Cloud which is about 180000 light-years away
Rememberhellip
A light-year is the distance that light travels in a vacuum in a year -- about 588 trillion miles (946 trillion kilometers)
An astronomical unit is 93 million miles or 150 million km (average distance between Sun and the Earth)
The speed (velocity) of light is 300000 kmsec
1048708Galaxies are classified based on shape
1 Spiral--rotating disk (with arms) 2 Ellipticalmdashspheroid or oval disk of
stars with more chaotic motion3 Irregular--none of the above
Three Main Types of Galaxies
Elliptical Spiral Irregular
Examples of Three Main Galaxy Types
Looking at the Milky WayA Spiral Galaxy
Viewed as a bright band of stars across the sky
There are about 200-400 billion stars in the Milky Way
Much of the Milky Way is blocked by dust seen as a dark band through the middle of the Milky Way1048708
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
bull Supergiant Large star with high
mass that become even hotter and expanding even more
It is 100rsquos of times hotter and more luminous than a red giant
Supernova
bull gigantic explosion in which a massive star collapses
ndash Occurs after a massive star uses up its fuel source
Supernova Remnant
White Dwarf
bull small hot star bull Fuel is used up
ndashFinal stage for some starsndashCan shine for billions of
years before they completely cool and extinguish
Black Dwarf
bull The remains of a white dwarf after it has completely cooledbull Scientists donot think universeis old enough tohave any black dwarfs yet
Neutron Star
A neutron star is a type of remnant that can result from the gravitational collapse of a massive star during a supernova event
Small dense star-one teaspoon would weigh a billion tons on Earth
What is a Black Hole
bull an object that is so massive that light cannot escape its gravity
Did you knowhellip
Astronomers can detect black holes by using X-ray telescopes
Pulsars
A neutron star that spins and sends out beams of radiation is called a pulsar
Hertzprung-Russell Diagram
Shows the relationship between a starrsquos surface temperature and absolute magnitude
ndash Used to study the lives of stars
ndash Most stars lie along the main sequence portion of the diagram
Our Place in Our Galaxy
Be careful about wishing on starshellip
Whatrsquos the Difference
Universe
Galaxy
Image credits NASA STScI
Solar System
Where is our Solar System
Visible stars gas dust in the Milky Way Galaxy
Image credits NASA STScI
Solar System
here
What Are Galaxies
bull A galaxy is a system of stars dust and gas held together by gravity
bull Galaxies are large collections of starshellip
millions and billions of stars
bull There are hundreds of billions of galaxies in the Universe
bull Millions to hundreds of billions of stars in each galaxy
Galaxy Factsbull The most distant galaxies ever photographed are as far as 10
billion to 13 billion light-years awaybull Large galaxies have more than a trillion stars bull Only three galaxies outside the Milky Way are visible with
the unaided eye People in the Northern Hemisphere can see the Andromeda Galaxy which is about 2 million light-years away People in the Southern Hemisphere can see the Large Magellanic Cloud which is about 160000 light-years from Earth and the Small Magellanic Cloud which is about 180000 light-years away
Rememberhellip
A light-year is the distance that light travels in a vacuum in a year -- about 588 trillion miles (946 trillion kilometers)
An astronomical unit is 93 million miles or 150 million km (average distance between Sun and the Earth)
The speed (velocity) of light is 300000 kmsec
1048708Galaxies are classified based on shape
1 Spiral--rotating disk (with arms) 2 Ellipticalmdashspheroid or oval disk of
stars with more chaotic motion3 Irregular--none of the above
Three Main Types of Galaxies
Elliptical Spiral Irregular
Examples of Three Main Galaxy Types
Looking at the Milky WayA Spiral Galaxy
Viewed as a bright band of stars across the sky
There are about 200-400 billion stars in the Milky Way
Much of the Milky Way is blocked by dust seen as a dark band through the middle of the Milky Way1048708
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
Supernova
bull gigantic explosion in which a massive star collapses
ndash Occurs after a massive star uses up its fuel source
Supernova Remnant
White Dwarf
bull small hot star bull Fuel is used up
ndashFinal stage for some starsndashCan shine for billions of
years before they completely cool and extinguish
Black Dwarf
bull The remains of a white dwarf after it has completely cooledbull Scientists donot think universeis old enough tohave any black dwarfs yet
Neutron Star
A neutron star is a type of remnant that can result from the gravitational collapse of a massive star during a supernova event
Small dense star-one teaspoon would weigh a billion tons on Earth
What is a Black Hole
bull an object that is so massive that light cannot escape its gravity
Did you knowhellip
Astronomers can detect black holes by using X-ray telescopes
Pulsars
A neutron star that spins and sends out beams of radiation is called a pulsar
Hertzprung-Russell Diagram
Shows the relationship between a starrsquos surface temperature and absolute magnitude
ndash Used to study the lives of stars
ndash Most stars lie along the main sequence portion of the diagram
Our Place in Our Galaxy
Be careful about wishing on starshellip
Whatrsquos the Difference
Universe
Galaxy
Image credits NASA STScI
Solar System
Where is our Solar System
Visible stars gas dust in the Milky Way Galaxy
Image credits NASA STScI
Solar System
here
What Are Galaxies
bull A galaxy is a system of stars dust and gas held together by gravity
bull Galaxies are large collections of starshellip
millions and billions of stars
bull There are hundreds of billions of galaxies in the Universe
bull Millions to hundreds of billions of stars in each galaxy
Galaxy Factsbull The most distant galaxies ever photographed are as far as 10
billion to 13 billion light-years awaybull Large galaxies have more than a trillion stars bull Only three galaxies outside the Milky Way are visible with
the unaided eye People in the Northern Hemisphere can see the Andromeda Galaxy which is about 2 million light-years away People in the Southern Hemisphere can see the Large Magellanic Cloud which is about 160000 light-years from Earth and the Small Magellanic Cloud which is about 180000 light-years away
Rememberhellip
A light-year is the distance that light travels in a vacuum in a year -- about 588 trillion miles (946 trillion kilometers)
An astronomical unit is 93 million miles or 150 million km (average distance between Sun and the Earth)
The speed (velocity) of light is 300000 kmsec
1048708Galaxies are classified based on shape
1 Spiral--rotating disk (with arms) 2 Ellipticalmdashspheroid or oval disk of
stars with more chaotic motion3 Irregular--none of the above
Three Main Types of Galaxies
Elliptical Spiral Irregular
Examples of Three Main Galaxy Types
Looking at the Milky WayA Spiral Galaxy
Viewed as a bright band of stars across the sky
There are about 200-400 billion stars in the Milky Way
Much of the Milky Way is blocked by dust seen as a dark band through the middle of the Milky Way1048708
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
Supernova Remnant
White Dwarf
bull small hot star bull Fuel is used up
ndashFinal stage for some starsndashCan shine for billions of
years before they completely cool and extinguish
Black Dwarf
bull The remains of a white dwarf after it has completely cooledbull Scientists donot think universeis old enough tohave any black dwarfs yet
Neutron Star
A neutron star is a type of remnant that can result from the gravitational collapse of a massive star during a supernova event
Small dense star-one teaspoon would weigh a billion tons on Earth
What is a Black Hole
bull an object that is so massive that light cannot escape its gravity
Did you knowhellip
Astronomers can detect black holes by using X-ray telescopes
Pulsars
A neutron star that spins and sends out beams of radiation is called a pulsar
Hertzprung-Russell Diagram
Shows the relationship between a starrsquos surface temperature and absolute magnitude
ndash Used to study the lives of stars
ndash Most stars lie along the main sequence portion of the diagram
Our Place in Our Galaxy
Be careful about wishing on starshellip
Whatrsquos the Difference
Universe
Galaxy
Image credits NASA STScI
Solar System
Where is our Solar System
Visible stars gas dust in the Milky Way Galaxy
Image credits NASA STScI
Solar System
here
What Are Galaxies
bull A galaxy is a system of stars dust and gas held together by gravity
bull Galaxies are large collections of starshellip
millions and billions of stars
bull There are hundreds of billions of galaxies in the Universe
bull Millions to hundreds of billions of stars in each galaxy
Galaxy Factsbull The most distant galaxies ever photographed are as far as 10
billion to 13 billion light-years awaybull Large galaxies have more than a trillion stars bull Only three galaxies outside the Milky Way are visible with
the unaided eye People in the Northern Hemisphere can see the Andromeda Galaxy which is about 2 million light-years away People in the Southern Hemisphere can see the Large Magellanic Cloud which is about 160000 light-years from Earth and the Small Magellanic Cloud which is about 180000 light-years away
Rememberhellip
A light-year is the distance that light travels in a vacuum in a year -- about 588 trillion miles (946 trillion kilometers)
An astronomical unit is 93 million miles or 150 million km (average distance between Sun and the Earth)
The speed (velocity) of light is 300000 kmsec
1048708Galaxies are classified based on shape
1 Spiral--rotating disk (with arms) 2 Ellipticalmdashspheroid or oval disk of
stars with more chaotic motion3 Irregular--none of the above
Three Main Types of Galaxies
Elliptical Spiral Irregular
Examples of Three Main Galaxy Types
Looking at the Milky WayA Spiral Galaxy
Viewed as a bright band of stars across the sky
There are about 200-400 billion stars in the Milky Way
Much of the Milky Way is blocked by dust seen as a dark band through the middle of the Milky Way1048708
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
White Dwarf
bull small hot star bull Fuel is used up
ndashFinal stage for some starsndashCan shine for billions of
years before they completely cool and extinguish
Black Dwarf
bull The remains of a white dwarf after it has completely cooledbull Scientists donot think universeis old enough tohave any black dwarfs yet
Neutron Star
A neutron star is a type of remnant that can result from the gravitational collapse of a massive star during a supernova event
Small dense star-one teaspoon would weigh a billion tons on Earth
What is a Black Hole
bull an object that is so massive that light cannot escape its gravity
Did you knowhellip
Astronomers can detect black holes by using X-ray telescopes
Pulsars
A neutron star that spins and sends out beams of radiation is called a pulsar
Hertzprung-Russell Diagram
Shows the relationship between a starrsquos surface temperature and absolute magnitude
ndash Used to study the lives of stars
ndash Most stars lie along the main sequence portion of the diagram
Our Place in Our Galaxy
Be careful about wishing on starshellip
Whatrsquos the Difference
Universe
Galaxy
Image credits NASA STScI
Solar System
Where is our Solar System
Visible stars gas dust in the Milky Way Galaxy
Image credits NASA STScI
Solar System
here
What Are Galaxies
bull A galaxy is a system of stars dust and gas held together by gravity
bull Galaxies are large collections of starshellip
millions and billions of stars
bull There are hundreds of billions of galaxies in the Universe
bull Millions to hundreds of billions of stars in each galaxy
Galaxy Factsbull The most distant galaxies ever photographed are as far as 10
billion to 13 billion light-years awaybull Large galaxies have more than a trillion stars bull Only three galaxies outside the Milky Way are visible with
the unaided eye People in the Northern Hemisphere can see the Andromeda Galaxy which is about 2 million light-years away People in the Southern Hemisphere can see the Large Magellanic Cloud which is about 160000 light-years from Earth and the Small Magellanic Cloud which is about 180000 light-years away
Rememberhellip
A light-year is the distance that light travels in a vacuum in a year -- about 588 trillion miles (946 trillion kilometers)
An astronomical unit is 93 million miles or 150 million km (average distance between Sun and the Earth)
The speed (velocity) of light is 300000 kmsec
1048708Galaxies are classified based on shape
1 Spiral--rotating disk (with arms) 2 Ellipticalmdashspheroid or oval disk of
stars with more chaotic motion3 Irregular--none of the above
Three Main Types of Galaxies
Elliptical Spiral Irregular
Examples of Three Main Galaxy Types
Looking at the Milky WayA Spiral Galaxy
Viewed as a bright band of stars across the sky
There are about 200-400 billion stars in the Milky Way
Much of the Milky Way is blocked by dust seen as a dark band through the middle of the Milky Way1048708
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
Black Dwarf
bull The remains of a white dwarf after it has completely cooledbull Scientists donot think universeis old enough tohave any black dwarfs yet
Neutron Star
A neutron star is a type of remnant that can result from the gravitational collapse of a massive star during a supernova event
Small dense star-one teaspoon would weigh a billion tons on Earth
What is a Black Hole
bull an object that is so massive that light cannot escape its gravity
Did you knowhellip
Astronomers can detect black holes by using X-ray telescopes
Pulsars
A neutron star that spins and sends out beams of radiation is called a pulsar
Hertzprung-Russell Diagram
Shows the relationship between a starrsquos surface temperature and absolute magnitude
ndash Used to study the lives of stars
ndash Most stars lie along the main sequence portion of the diagram
Our Place in Our Galaxy
Be careful about wishing on starshellip
Whatrsquos the Difference
Universe
Galaxy
Image credits NASA STScI
Solar System
Where is our Solar System
Visible stars gas dust in the Milky Way Galaxy
Image credits NASA STScI
Solar System
here
What Are Galaxies
bull A galaxy is a system of stars dust and gas held together by gravity
bull Galaxies are large collections of starshellip
millions and billions of stars
bull There are hundreds of billions of galaxies in the Universe
bull Millions to hundreds of billions of stars in each galaxy
Galaxy Factsbull The most distant galaxies ever photographed are as far as 10
billion to 13 billion light-years awaybull Large galaxies have more than a trillion stars bull Only three galaxies outside the Milky Way are visible with
the unaided eye People in the Northern Hemisphere can see the Andromeda Galaxy which is about 2 million light-years away People in the Southern Hemisphere can see the Large Magellanic Cloud which is about 160000 light-years from Earth and the Small Magellanic Cloud which is about 180000 light-years away
Rememberhellip
A light-year is the distance that light travels in a vacuum in a year -- about 588 trillion miles (946 trillion kilometers)
An astronomical unit is 93 million miles or 150 million km (average distance between Sun and the Earth)
The speed (velocity) of light is 300000 kmsec
1048708Galaxies are classified based on shape
1 Spiral--rotating disk (with arms) 2 Ellipticalmdashspheroid or oval disk of
stars with more chaotic motion3 Irregular--none of the above
Three Main Types of Galaxies
Elliptical Spiral Irregular
Examples of Three Main Galaxy Types
Looking at the Milky WayA Spiral Galaxy
Viewed as a bright band of stars across the sky
There are about 200-400 billion stars in the Milky Way
Much of the Milky Way is blocked by dust seen as a dark band through the middle of the Milky Way1048708
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
Neutron Star
A neutron star is a type of remnant that can result from the gravitational collapse of a massive star during a supernova event
Small dense star-one teaspoon would weigh a billion tons on Earth
What is a Black Hole
bull an object that is so massive that light cannot escape its gravity
Did you knowhellip
Astronomers can detect black holes by using X-ray telescopes
Pulsars
A neutron star that spins and sends out beams of radiation is called a pulsar
Hertzprung-Russell Diagram
Shows the relationship between a starrsquos surface temperature and absolute magnitude
ndash Used to study the lives of stars
ndash Most stars lie along the main sequence portion of the diagram
Our Place in Our Galaxy
Be careful about wishing on starshellip
Whatrsquos the Difference
Universe
Galaxy
Image credits NASA STScI
Solar System
Where is our Solar System
Visible stars gas dust in the Milky Way Galaxy
Image credits NASA STScI
Solar System
here
What Are Galaxies
bull A galaxy is a system of stars dust and gas held together by gravity
bull Galaxies are large collections of starshellip
millions and billions of stars
bull There are hundreds of billions of galaxies in the Universe
bull Millions to hundreds of billions of stars in each galaxy
Galaxy Factsbull The most distant galaxies ever photographed are as far as 10
billion to 13 billion light-years awaybull Large galaxies have more than a trillion stars bull Only three galaxies outside the Milky Way are visible with
the unaided eye People in the Northern Hemisphere can see the Andromeda Galaxy which is about 2 million light-years away People in the Southern Hemisphere can see the Large Magellanic Cloud which is about 160000 light-years from Earth and the Small Magellanic Cloud which is about 180000 light-years away
Rememberhellip
A light-year is the distance that light travels in a vacuum in a year -- about 588 trillion miles (946 trillion kilometers)
An astronomical unit is 93 million miles or 150 million km (average distance between Sun and the Earth)
The speed (velocity) of light is 300000 kmsec
1048708Galaxies are classified based on shape
1 Spiral--rotating disk (with arms) 2 Ellipticalmdashspheroid or oval disk of
stars with more chaotic motion3 Irregular--none of the above
Three Main Types of Galaxies
Elliptical Spiral Irregular
Examples of Three Main Galaxy Types
Looking at the Milky WayA Spiral Galaxy
Viewed as a bright band of stars across the sky
There are about 200-400 billion stars in the Milky Way
Much of the Milky Way is blocked by dust seen as a dark band through the middle of the Milky Way1048708
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
What is a Black Hole
bull an object that is so massive that light cannot escape its gravity
Did you knowhellip
Astronomers can detect black holes by using X-ray telescopes
Pulsars
A neutron star that spins and sends out beams of radiation is called a pulsar
Hertzprung-Russell Diagram
Shows the relationship between a starrsquos surface temperature and absolute magnitude
ndash Used to study the lives of stars
ndash Most stars lie along the main sequence portion of the diagram
Our Place in Our Galaxy
Be careful about wishing on starshellip
Whatrsquos the Difference
Universe
Galaxy
Image credits NASA STScI
Solar System
Where is our Solar System
Visible stars gas dust in the Milky Way Galaxy
Image credits NASA STScI
Solar System
here
What Are Galaxies
bull A galaxy is a system of stars dust and gas held together by gravity
bull Galaxies are large collections of starshellip
millions and billions of stars
bull There are hundreds of billions of galaxies in the Universe
bull Millions to hundreds of billions of stars in each galaxy
Galaxy Factsbull The most distant galaxies ever photographed are as far as 10
billion to 13 billion light-years awaybull Large galaxies have more than a trillion stars bull Only three galaxies outside the Milky Way are visible with
the unaided eye People in the Northern Hemisphere can see the Andromeda Galaxy which is about 2 million light-years away People in the Southern Hemisphere can see the Large Magellanic Cloud which is about 160000 light-years from Earth and the Small Magellanic Cloud which is about 180000 light-years away
Rememberhellip
A light-year is the distance that light travels in a vacuum in a year -- about 588 trillion miles (946 trillion kilometers)
An astronomical unit is 93 million miles or 150 million km (average distance between Sun and the Earth)
The speed (velocity) of light is 300000 kmsec
1048708Galaxies are classified based on shape
1 Spiral--rotating disk (with arms) 2 Ellipticalmdashspheroid or oval disk of
stars with more chaotic motion3 Irregular--none of the above
Three Main Types of Galaxies
Elliptical Spiral Irregular
Examples of Three Main Galaxy Types
Looking at the Milky WayA Spiral Galaxy
Viewed as a bright band of stars across the sky
There are about 200-400 billion stars in the Milky Way
Much of the Milky Way is blocked by dust seen as a dark band through the middle of the Milky Way1048708
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
Pulsars
A neutron star that spins and sends out beams of radiation is called a pulsar
Hertzprung-Russell Diagram
Shows the relationship between a starrsquos surface temperature and absolute magnitude
ndash Used to study the lives of stars
ndash Most stars lie along the main sequence portion of the diagram
Our Place in Our Galaxy
Be careful about wishing on starshellip
Whatrsquos the Difference
Universe
Galaxy
Image credits NASA STScI
Solar System
Where is our Solar System
Visible stars gas dust in the Milky Way Galaxy
Image credits NASA STScI
Solar System
here
What Are Galaxies
bull A galaxy is a system of stars dust and gas held together by gravity
bull Galaxies are large collections of starshellip
millions and billions of stars
bull There are hundreds of billions of galaxies in the Universe
bull Millions to hundreds of billions of stars in each galaxy
Galaxy Factsbull The most distant galaxies ever photographed are as far as 10
billion to 13 billion light-years awaybull Large galaxies have more than a trillion stars bull Only three galaxies outside the Milky Way are visible with
the unaided eye People in the Northern Hemisphere can see the Andromeda Galaxy which is about 2 million light-years away People in the Southern Hemisphere can see the Large Magellanic Cloud which is about 160000 light-years from Earth and the Small Magellanic Cloud which is about 180000 light-years away
Rememberhellip
A light-year is the distance that light travels in a vacuum in a year -- about 588 trillion miles (946 trillion kilometers)
An astronomical unit is 93 million miles or 150 million km (average distance between Sun and the Earth)
The speed (velocity) of light is 300000 kmsec
1048708Galaxies are classified based on shape
1 Spiral--rotating disk (with arms) 2 Ellipticalmdashspheroid or oval disk of
stars with more chaotic motion3 Irregular--none of the above
Three Main Types of Galaxies
Elliptical Spiral Irregular
Examples of Three Main Galaxy Types
Looking at the Milky WayA Spiral Galaxy
Viewed as a bright band of stars across the sky
There are about 200-400 billion stars in the Milky Way
Much of the Milky Way is blocked by dust seen as a dark band through the middle of the Milky Way1048708
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
Hertzprung-Russell Diagram
Shows the relationship between a starrsquos surface temperature and absolute magnitude
ndash Used to study the lives of stars
ndash Most stars lie along the main sequence portion of the diagram
Our Place in Our Galaxy
Be careful about wishing on starshellip
Whatrsquos the Difference
Universe
Galaxy
Image credits NASA STScI
Solar System
Where is our Solar System
Visible stars gas dust in the Milky Way Galaxy
Image credits NASA STScI
Solar System
here
What Are Galaxies
bull A galaxy is a system of stars dust and gas held together by gravity
bull Galaxies are large collections of starshellip
millions and billions of stars
bull There are hundreds of billions of galaxies in the Universe
bull Millions to hundreds of billions of stars in each galaxy
Galaxy Factsbull The most distant galaxies ever photographed are as far as 10
billion to 13 billion light-years awaybull Large galaxies have more than a trillion stars bull Only three galaxies outside the Milky Way are visible with
the unaided eye People in the Northern Hemisphere can see the Andromeda Galaxy which is about 2 million light-years away People in the Southern Hemisphere can see the Large Magellanic Cloud which is about 160000 light-years from Earth and the Small Magellanic Cloud which is about 180000 light-years away
Rememberhellip
A light-year is the distance that light travels in a vacuum in a year -- about 588 trillion miles (946 trillion kilometers)
An astronomical unit is 93 million miles or 150 million km (average distance between Sun and the Earth)
The speed (velocity) of light is 300000 kmsec
1048708Galaxies are classified based on shape
1 Spiral--rotating disk (with arms) 2 Ellipticalmdashspheroid or oval disk of
stars with more chaotic motion3 Irregular--none of the above
Three Main Types of Galaxies
Elliptical Spiral Irregular
Examples of Three Main Galaxy Types
Looking at the Milky WayA Spiral Galaxy
Viewed as a bright band of stars across the sky
There are about 200-400 billion stars in the Milky Way
Much of the Milky Way is blocked by dust seen as a dark band through the middle of the Milky Way1048708
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
Our Place in Our Galaxy
Be careful about wishing on starshellip
Whatrsquos the Difference
Universe
Galaxy
Image credits NASA STScI
Solar System
Where is our Solar System
Visible stars gas dust in the Milky Way Galaxy
Image credits NASA STScI
Solar System
here
What Are Galaxies
bull A galaxy is a system of stars dust and gas held together by gravity
bull Galaxies are large collections of starshellip
millions and billions of stars
bull There are hundreds of billions of galaxies in the Universe
bull Millions to hundreds of billions of stars in each galaxy
Galaxy Factsbull The most distant galaxies ever photographed are as far as 10
billion to 13 billion light-years awaybull Large galaxies have more than a trillion stars bull Only three galaxies outside the Milky Way are visible with
the unaided eye People in the Northern Hemisphere can see the Andromeda Galaxy which is about 2 million light-years away People in the Southern Hemisphere can see the Large Magellanic Cloud which is about 160000 light-years from Earth and the Small Magellanic Cloud which is about 180000 light-years away
Rememberhellip
A light-year is the distance that light travels in a vacuum in a year -- about 588 trillion miles (946 trillion kilometers)
An astronomical unit is 93 million miles or 150 million km (average distance between Sun and the Earth)
The speed (velocity) of light is 300000 kmsec
1048708Galaxies are classified based on shape
1 Spiral--rotating disk (with arms) 2 Ellipticalmdashspheroid or oval disk of
stars with more chaotic motion3 Irregular--none of the above
Three Main Types of Galaxies
Elliptical Spiral Irregular
Examples of Three Main Galaxy Types
Looking at the Milky WayA Spiral Galaxy
Viewed as a bright band of stars across the sky
There are about 200-400 billion stars in the Milky Way
Much of the Milky Way is blocked by dust seen as a dark band through the middle of the Milky Way1048708
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
Be careful about wishing on starshellip
Whatrsquos the Difference
Universe
Galaxy
Image credits NASA STScI
Solar System
Where is our Solar System
Visible stars gas dust in the Milky Way Galaxy
Image credits NASA STScI
Solar System
here
What Are Galaxies
bull A galaxy is a system of stars dust and gas held together by gravity
bull Galaxies are large collections of starshellip
millions and billions of stars
bull There are hundreds of billions of galaxies in the Universe
bull Millions to hundreds of billions of stars in each galaxy
Galaxy Factsbull The most distant galaxies ever photographed are as far as 10
billion to 13 billion light-years awaybull Large galaxies have more than a trillion stars bull Only three galaxies outside the Milky Way are visible with
the unaided eye People in the Northern Hemisphere can see the Andromeda Galaxy which is about 2 million light-years away People in the Southern Hemisphere can see the Large Magellanic Cloud which is about 160000 light-years from Earth and the Small Magellanic Cloud which is about 180000 light-years away
Rememberhellip
A light-year is the distance that light travels in a vacuum in a year -- about 588 trillion miles (946 trillion kilometers)
An astronomical unit is 93 million miles or 150 million km (average distance between Sun and the Earth)
The speed (velocity) of light is 300000 kmsec
1048708Galaxies are classified based on shape
1 Spiral--rotating disk (with arms) 2 Ellipticalmdashspheroid or oval disk of
stars with more chaotic motion3 Irregular--none of the above
Three Main Types of Galaxies
Elliptical Spiral Irregular
Examples of Three Main Galaxy Types
Looking at the Milky WayA Spiral Galaxy
Viewed as a bright band of stars across the sky
There are about 200-400 billion stars in the Milky Way
Much of the Milky Way is blocked by dust seen as a dark band through the middle of the Milky Way1048708
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
Whatrsquos the Difference
Universe
Galaxy
Image credits NASA STScI
Solar System
Where is our Solar System
Visible stars gas dust in the Milky Way Galaxy
Image credits NASA STScI
Solar System
here
What Are Galaxies
bull A galaxy is a system of stars dust and gas held together by gravity
bull Galaxies are large collections of starshellip
millions and billions of stars
bull There are hundreds of billions of galaxies in the Universe
bull Millions to hundreds of billions of stars in each galaxy
Galaxy Factsbull The most distant galaxies ever photographed are as far as 10
billion to 13 billion light-years awaybull Large galaxies have more than a trillion stars bull Only three galaxies outside the Milky Way are visible with
the unaided eye People in the Northern Hemisphere can see the Andromeda Galaxy which is about 2 million light-years away People in the Southern Hemisphere can see the Large Magellanic Cloud which is about 160000 light-years from Earth and the Small Magellanic Cloud which is about 180000 light-years away
Rememberhellip
A light-year is the distance that light travels in a vacuum in a year -- about 588 trillion miles (946 trillion kilometers)
An astronomical unit is 93 million miles or 150 million km (average distance between Sun and the Earth)
The speed (velocity) of light is 300000 kmsec
1048708Galaxies are classified based on shape
1 Spiral--rotating disk (with arms) 2 Ellipticalmdashspheroid or oval disk of
stars with more chaotic motion3 Irregular--none of the above
Three Main Types of Galaxies
Elliptical Spiral Irregular
Examples of Three Main Galaxy Types
Looking at the Milky WayA Spiral Galaxy
Viewed as a bright band of stars across the sky
There are about 200-400 billion stars in the Milky Way
Much of the Milky Way is blocked by dust seen as a dark band through the middle of the Milky Way1048708
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
Where is our Solar System
Visible stars gas dust in the Milky Way Galaxy
Image credits NASA STScI
Solar System
here
What Are Galaxies
bull A galaxy is a system of stars dust and gas held together by gravity
bull Galaxies are large collections of starshellip
millions and billions of stars
bull There are hundreds of billions of galaxies in the Universe
bull Millions to hundreds of billions of stars in each galaxy
Galaxy Factsbull The most distant galaxies ever photographed are as far as 10
billion to 13 billion light-years awaybull Large galaxies have more than a trillion stars bull Only three galaxies outside the Milky Way are visible with
the unaided eye People in the Northern Hemisphere can see the Andromeda Galaxy which is about 2 million light-years away People in the Southern Hemisphere can see the Large Magellanic Cloud which is about 160000 light-years from Earth and the Small Magellanic Cloud which is about 180000 light-years away
Rememberhellip
A light-year is the distance that light travels in a vacuum in a year -- about 588 trillion miles (946 trillion kilometers)
An astronomical unit is 93 million miles or 150 million km (average distance between Sun and the Earth)
The speed (velocity) of light is 300000 kmsec
1048708Galaxies are classified based on shape
1 Spiral--rotating disk (with arms) 2 Ellipticalmdashspheroid or oval disk of
stars with more chaotic motion3 Irregular--none of the above
Three Main Types of Galaxies
Elliptical Spiral Irregular
Examples of Three Main Galaxy Types
Looking at the Milky WayA Spiral Galaxy
Viewed as a bright band of stars across the sky
There are about 200-400 billion stars in the Milky Way
Much of the Milky Way is blocked by dust seen as a dark band through the middle of the Milky Way1048708
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
What Are Galaxies
bull A galaxy is a system of stars dust and gas held together by gravity
bull Galaxies are large collections of starshellip
millions and billions of stars
bull There are hundreds of billions of galaxies in the Universe
bull Millions to hundreds of billions of stars in each galaxy
Galaxy Factsbull The most distant galaxies ever photographed are as far as 10
billion to 13 billion light-years awaybull Large galaxies have more than a trillion stars bull Only three galaxies outside the Milky Way are visible with
the unaided eye People in the Northern Hemisphere can see the Andromeda Galaxy which is about 2 million light-years away People in the Southern Hemisphere can see the Large Magellanic Cloud which is about 160000 light-years from Earth and the Small Magellanic Cloud which is about 180000 light-years away
Rememberhellip
A light-year is the distance that light travels in a vacuum in a year -- about 588 trillion miles (946 trillion kilometers)
An astronomical unit is 93 million miles or 150 million km (average distance between Sun and the Earth)
The speed (velocity) of light is 300000 kmsec
1048708Galaxies are classified based on shape
1 Spiral--rotating disk (with arms) 2 Ellipticalmdashspheroid or oval disk of
stars with more chaotic motion3 Irregular--none of the above
Three Main Types of Galaxies
Elliptical Spiral Irregular
Examples of Three Main Galaxy Types
Looking at the Milky WayA Spiral Galaxy
Viewed as a bright band of stars across the sky
There are about 200-400 billion stars in the Milky Way
Much of the Milky Way is blocked by dust seen as a dark band through the middle of the Milky Way1048708
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
Galaxy Factsbull The most distant galaxies ever photographed are as far as 10
billion to 13 billion light-years awaybull Large galaxies have more than a trillion stars bull Only three galaxies outside the Milky Way are visible with
the unaided eye People in the Northern Hemisphere can see the Andromeda Galaxy which is about 2 million light-years away People in the Southern Hemisphere can see the Large Magellanic Cloud which is about 160000 light-years from Earth and the Small Magellanic Cloud which is about 180000 light-years away
Rememberhellip
A light-year is the distance that light travels in a vacuum in a year -- about 588 trillion miles (946 trillion kilometers)
An astronomical unit is 93 million miles or 150 million km (average distance between Sun and the Earth)
The speed (velocity) of light is 300000 kmsec
1048708Galaxies are classified based on shape
1 Spiral--rotating disk (with arms) 2 Ellipticalmdashspheroid or oval disk of
stars with more chaotic motion3 Irregular--none of the above
Three Main Types of Galaxies
Elliptical Spiral Irregular
Examples of Three Main Galaxy Types
Looking at the Milky WayA Spiral Galaxy
Viewed as a bright band of stars across the sky
There are about 200-400 billion stars in the Milky Way
Much of the Milky Way is blocked by dust seen as a dark band through the middle of the Milky Way1048708
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
1048708Galaxies are classified based on shape
1 Spiral--rotating disk (with arms) 2 Ellipticalmdashspheroid or oval disk of
stars with more chaotic motion3 Irregular--none of the above
Three Main Types of Galaxies
Elliptical Spiral Irregular
Examples of Three Main Galaxy Types
Looking at the Milky WayA Spiral Galaxy
Viewed as a bright band of stars across the sky
There are about 200-400 billion stars in the Milky Way
Much of the Milky Way is blocked by dust seen as a dark band through the middle of the Milky Way1048708
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
Elliptical Spiral Irregular
Examples of Three Main Galaxy Types
Looking at the Milky WayA Spiral Galaxy
Viewed as a bright band of stars across the sky
There are about 200-400 billion stars in the Milky Way
Much of the Milky Way is blocked by dust seen as a dark band through the middle of the Milky Way1048708
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
Looking at the Milky WayA Spiral Galaxy
Viewed as a bright band of stars across the sky
There are about 200-400 billion stars in the Milky Way
Much of the Milky Way is blocked by dust seen as a dark band through the middle of the Milky Way1048708
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
The Milky Way ishellip
bull Gigantic Its disk spans 100000 light-yearsbull itrsquos about 14 billion years old give or take a few
billionndash Astronomers arrived at this age by measuring the age
of a single star The galaxy canrsquot be any YOUNGER than its oldest stars so this technique yields a MINIMUM age for the Milky Way
ndash Astronomers determined the starrsquos age by measuring its chemistry They found that it contains only minute traces of anything heavier than hydrogen and helium the two lightest elements
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
One of the most important tracers of the starrsquos age is a radioactive element called thoriumThe star contains only about half as much thorium as expectedThorium has a half-life of 14 billion years In other words in 14 billion years half the starrsquos thorium should have turned into other elements Since half of the thorium has disappeared astronomers deduce that the star is about 14 billion years old mdash and so is the Milky Way
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
If gasdust in a disk are rotating with the same speed stuff further out will take longer to go around and will lag behind
Spiral arms are a natural consequence of some rotations
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
Elliptical Galaxies
lack spiral arms and dust andcontain
stars that are
generally identified
asbeing old
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-
Irregular GalaxiesIrregular galaxies lack any specific form and contain stars gas and dust
- PowerPoint Presentation
- Slide 2
- Hydrostatic Equilibrium
- NEBULA
- 1st Stage of Life
- Slide 6
- 2nd Stage
- A Star of a Jokehellip
- 3rd stage
- Slide 10
- Slide 11
- Supernova
- Supernova Remnant
- White Dwarf
- Slide 15
- Black Dwarf
- Neutron Star
- What is a Black Hole
- Slide 19
- Pulsars
- Hertzprung-Russell Diagram
- Slide 22
- Our Place in Our Galaxy
- Be careful about wishing on starshellip
- Whatrsquos the Difference
- Where is our Solar System
- What Are Galaxies
- Slide 28
- Galaxy Facts
- Slide 30
- Slide 31
- Three Main Types of Galaxies
- Slide 33
- Looking at the Milky Way A Spiral Galaxy
- The Milky Way ishellip
- Slide 36
- Slide 37
- Slide 38
- Slide 39
- Slide 40
- Elliptical Galaxies
- Irregular Galaxies
-