the big bang!
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The Big Bang!. Origins. How and when did the: universe form? solar system / Earth form? Moon form? What were early Earth conditions? How Do We Know?. Origin of the Universe. Big Bang occurred 15 billion years ago model for the beginning of the universe. Building a Universe. - PowerPoint PPT PresentationTRANSCRIPT
The Big Bang!The Big Bang!
OriginsOrigins How and when did the:
universe form?
solar system / Earth form?
Moon form?
What were early Earth conditions?
How Do We Know?
How and when did the:
universe form?
solar system / Earth form?
Moon form?
What were early Earth conditions?
How Do We Know?
Origin of the UniverseOrigin of the Universe
Big Bang occurred 15 billion years ago model for the beginning of the universe
Big Bang occurred 15 billion years ago model for the beginning of the universe
http://rainbow.ldeo.columbia.edu/courses/v1001/7.html
- infinitely dense point not governed by our physical laws or time
- all matter and energy contained in one point
Building a UniverseBuilding a Universe
http://rainbow.ldeo.columbia.edu/courses/v1001/7.html
- instantaneous filling of space with all matter
Building a Universe
Edwin HubbleEdwin Hubble
Universe is continuously expanding
Galaxy’s velocity is proportional to its distance (galaxies that are twice as far from us move twice as fast) taken every galaxy the same amount of time to move from a common starting position to its current position
Universe is continuously expanding
Galaxy’s velocity is proportional to its distance (galaxies that are twice as far from us move twice as fast) taken every galaxy the same amount of time to move from a common starting position to its current position
Hubble’s EvidenceHubble’s Evidence
Doppler shifting - wavelength emitted by something moving away from us is shifted to a lower frequency
Sound of a fire truck siren - pitch of the siren is higher as the fire truck moves towards you, and lower as it moves away from you
Visible wavelengths emitted by objects moving away from us are shifted towards the red part of the visible spectrum
The faster they move away from us, the more they are redshifted. Thus, redshift is a reasonable way to measure the speed of an object (this, by the way, is the principal by which radar guns measure the speed of a car or baseball)
When we observe the redshift of galaxies outside our local group, every galaxy appears to be moving away from us - universe is expanding.
Doppler shifting - wavelength emitted by something moving away from us is shifted to a lower frequency
Sound of a fire truck siren - pitch of the siren is higher as the fire truck moves towards you, and lower as it moves away from you
Visible wavelengths emitted by objects moving away from us are shifted towards the red part of the visible spectrum
The faster they move away from us, the more they are redshifted. Thus, redshift is a reasonable way to measure the speed of an object (this, by the way, is the principal by which radar guns measure the speed of a car or baseball)
When we observe the redshift of galaxies outside our local group, every galaxy appears to be moving away from us - universe is expanding.
Evidence for Big BangEvidence for Big Bang
Red shift - as light from distant galaxies approach earth there is an increase of space between earth and the galaxy, which leads to wavelengths being stretched
In 1964, Arno Penzias and Robert Wilson, discovered a noise of extraterrestrial origin that came from all directions at once - radiation left over from the Big Bang
In June 1995, scientists detected primordial helium in the far reaches of the universe - consistent with an important aspect of the Big Bang theory that a mixture of hydrogen and helium was created at the beginning of the universe
Red shift - as light from distant galaxies approach earth there is an increase of space between earth and the galaxy, which leads to wavelengths being stretched
In 1964, Arno Penzias and Robert Wilson, discovered a noise of extraterrestrial origin that came from all directions at once - radiation left over from the Big Bang
In June 1995, scientists detected primordial helium in the far reaches of the universe - consistent with an important aspect of the Big Bang theory that a mixture of hydrogen and helium was created at the beginning of the universe
Building a
Universe
Building a
Universe
•10-43 s - gravity separates from other forces - 10-28 centimeters
•10-35 to 10-32 s - fundamental particles - quarks and electrons - softball
•10-6 s - quarks combine into protons and neutrons - solar system
•1 s - electromagnetic and weak nuclear forces separate
•3 minutes - protons and neutrons combine into atomic nuclei
•105 years - electrons join nuclei to make atoms; light is emitted
•105-109 years - matter collapses into clouds, making galaxies and stars
Orion Nebula - http://stardate.utexas.edu/resources/ssguide/planet_form.html
When Did the Universe Form?
When Did the Universe Form?
10 to 20 billion years ago (15)
How do we know? spreading (Red Shift) know distances, rates of retreat, relative positions
pervasive background radiation of 2.7°C above absolute zero
afterglow of the Big Bang
10 to 20 billion years ago (15)
How do we know? spreading (Red Shift) know distances, rates of retreat, relative positions
pervasive background radiation of 2.7°C above absolute zero
afterglow of the Big Bang
Orion Nebula - http://stardate.utexas.edu/resources/ssguide/planet_form.html
How old is the universe?How old is the universe?
Speed x time = distance (distance of a particular galaxy) / (that galaxy’s velocity) = (time) or
4.6 x 10^26 cm / 1 x 10^9 cm/sec = 4.6 x 10^17 sec ~ 15 billion years
Speed x time = distance (distance of a particular galaxy) / (that galaxy’s velocity) = (time) or
4.6 x 10^26 cm / 1 x 10^9 cm/sec = 4.6 x 10^17 sec ~ 15 billion years
Features of Our Solar System
Features of Our Solar System
in a spiral arm of the Milky Way Galaxy
Sun 9 planets 101 known moons (satellites) a tremendous number of asteroids
most orbit the Sun between the orbits of Mars and Jupiter
millions of comets and meteorites interplanetary dust and gases
in a spiral arm of the Milky Way Galaxy
Sun 9 planets 101 known moons (satellites) a tremendous number of asteroids
most orbit the Sun between the orbits of Mars and Jupiter
millions of comets and meteorites interplanetary dust and gases
Relative Sizes of the Sun and Planets
Relative Sizes of the Sun and Planets
Solar System ConfigurationSolar System Configuration
Origin of Our Solar System
Origin of Our Solar System
Solar nebula theorySolar nebula theory
formed a rotating diskcondensed and collapsed due to gravity
forming solar nebula with an embryonic Sun surrounded by a rotating cloud
cloud of gases and dust
planetesimals have formed in the inner solar system
large eddies of gas and dust remain far from the protosun
planetesimals have formed in the inner solar system
large eddies of gas and dust remain far from the protosun
Embryonic Sun and Rotating Cloud
Embryonic Sun and Rotating Cloud
The PlanetsThe Planets
Terrestrial Planets Mercury Venus Earth Mars
small, composed of rock, with metal cores
Terrestrial Planets Mercury Venus Earth Mars
small, composed of rock, with metal cores
Jovian PlanetsJupiter SaturnUranusNeptune
large, composed of hydrogen, helium, ammonia, methane, relatively small rocky cores
– Pluto?