the basics. a planet is an object that orbits a star large enough to become rounded by its own...
TRANSCRIPT
Our Solar SystemThe Basics
Our Solar System
What’s with Pluto?
Only one star
What is a planet?
A planet is an object that orbits a star
Large enough to become rounded by its own gravity
Able to clear its own orbit of objects, such as asteroids, meteoroids, other space junk!
What’s with Pluto?To be a planet…
1. The object must be in orbit around the Sun.
Well, Pluto does that!
2. A "planet" has to be big enough that gravity squeezes it into a round shape. Well, Pluto does that.
3. A planet must be big enough that it's gravity removes other objects that occupy the same orbit.
But Pluto does not meet this criterion.
Poor Pluto…
So, Pluto is considered to be a DWARF PLANET
And just to give you an idea…
And just to give you an idea…
And just to give you an idea…
And just to give you an idea…
And just to give you an idea…
Our Galaxy- The Milky Way
Our galaxy - the Milky Way - is a spiral galaxy with arms extending from the center like a pinwheel. Our solar system is in the Orion arm of the Milky Way. Our Sun is one of about 100 billion stars in the Milky Way. And our galaxy is just one of roughly 100 billion in the visible universe.
Parking Lot Questions
What is at the center of the galaxy?The Galactic Center harbors a variety of intriguing puzzles,
including a strangely quiescent supermassive black hole, a
collection of wispy magnetic filaments, a few dense stellar
superclusters which host mysterious and massive stars, a star with a tail, and a family of
gas streamers spiraling toward a central dark mass.
Pre-AssessmentSun-Earth-Moon
The Sun-Earth-Moon System
The Sun
Parking Lot Questions
How long does it take for light from the sun to travel to Earth?
The sun's light takes about 8 minutes to reach the Earth after it has been emitted from the sun's surface. The time it takes
for light to reach planets in our Solar System (not the Milky Way, which is our galaxy) varies from about 3 minutes for Mercury, to about 5.3 hours for Pluto.
The SunThe only STAR in our solar system!
NewSong
OldSong
Sun Facts:
Eventually, the Sun will consume the Earth:When all the Hydrogen has been burned, the Sun will continue for about 130 million more years, burning Helium, during which time it will expand to the point that it will engulf Mercury and Venus and the Earth. At this stage it will have become a red giant
Sun Facts:
The Sun will one day be about the size of Earth:After its red giant phase, the Sun will collapse, retaining its enormous mass, but containing the approximate volume of our planet. When this happens, it will be called a white dwarf.
The Sun- Did you know?
Age: 4.6 Billion YearsType: Yellow Dwarf (G2V)Diameter: 1,392,684 kmCircumference at Equator: 4,370,005.6 kmMass: 1,989,100,000,000,000,000,000 billion kg (333,060 x Earth)Surface Temperature: 5500 °C
The Sun’s Revolution
The Sun and the entire solar system orbits around the center of the Milky Way galaxy. The average velocity of the solar system is 828,000 km/hr. At that rate it will take about 230 million years to make one complete orbit around the galaxy.
The Earth
Earth Facts:
Earth is the third planet from the Sun and is the largest of the terrestrial planets. Unlike the other planets in the solar system that are named after classic deities the Earth’s name comes from the Anglo-Saxon worderda which means ground or soil. The Earth was formed approximately 4.54 billion years ago and is the only known planet to support life.
Earth Facts:
Mass: 5,972,190,000,000,000 billion kgEquatorial Diameter: 12,756 kmPolar Diameter: 12,714 kmEquatorial Circumference: 40,030 kmKnown Satellites: 1Notable Satellites: The MoonOrbit Distance: 149,598,262 km (1 AU)Orbit Period: 365.26 Earth daysSurface Temperature: -88 to 58°C
Earth Facts:
The Earth’s rotation is gradually slowing:This deceleration is happening almost imperceptibly, at approximately 17 milliseconds per hundred years, although the rate at which it occurs is not perfectly uniform. This has the effect of lengthening our days, but it happens so slowly that it could be as much as 140 million years before the length of a day will have increased to 25 hours.
The Moon
Moon Facts:
The Moon (or Luna) is the Earth’s only natural satellite and was formed 4.6 billion years ago around some 30–50 million years after the formation of the solar system. The Moon is in synchronous rotation with Earth meaning the same side is always facing the Earth. The first unmanned mission to the Moon was in 1959 by the Soviet Lunar Program with the first manned landing being Apollo 11 in 1969.
Moon Facts: Where did it come from?
Giant impact hypothesis: This is the theory that a giant planetoid collided with the Earth billions of years ago, blasting out a cloud of debris that collected into the Moon.
https://www.youtube.com/watch?v=hahpE8b6fDI
Moon Facts:
Circumference at Equator: 10,917.0 kmDiameter: 3,475 kmMass: 73,476,730,924,573,500 million kg
(0.0123 x Earth)Average Distance from Earth: 384,400 kmLength of Orbit: 27.3 Earth daysSurface Temperature: -233 to 123 °C
Moon Facts:
The rise and fall of the tides on Earth is caused by the Moon:There are two bulges in the Earth due to the gravitational pull that the Moon exerts; one on the side facing the Moon, and the other on the opposite side that faces away from the Moon, The bulges move around the oceans as the Earth rotates, causing high and low tides around the globe.
Moon Facts:
The Moon is drifting away from the Earth:The Moon is moving approximately 3.8 cm away from our planet every year. It is estimated that it will continue to do so for around 50 billion years. By the time that happens, the Moon will be taking around 47 days to orbit the Earth instead of the current 27.3 days.
Moon Facts
The Moon has no atmosphere:This means that the surface of the Moon is unprotected from cosmic rays, meteorites and solar winds, and has huge temperature variations. The lack of atmosphere means no sound can be heard on the Moon, and the sky always appears black.
Sun-Earth-Moon Vocab Review