Solar System Sun, Planets, Minor Planets, Asteroids, Comets, Meteors and Lots of Space

But first… What you do affect the people around you, and some students want to participate in this class –If you want to talk, please leave the room. Do not stand in a doorway. –If you want to text your friends, please leave the room. Please be considerate of the other students in the class. –If you want to listen to music, please do so somewhere else. You may be using headphones, but we still can hear. –If you want to use your computer for anything other than note taking, please go somewhere else.

Visible From Earth Sun Moon 5 Planets Stars Satellites and ISS Constellations 3 Galaxies December 4, 1997

Galaxies Large Magellanic Cloud Small Magellanic Cloud Andromeda Galaxy (found in the Constellation Andromda

Andromeda Galaxy 2.2 million light years away ~13,200,000,000,000,000,000 miles 13 quintillion miles

Polaris Within 1º of our polar north Not always the “north star”

Procession Wobble like a top Completes the wobble every ~26,000 years Other “north stars, Thuban in Draco and Vega in Lyra However, they are no where near 1º of our polar north

Constellations Star patterns in sky Acts like state lines in a road map Stars appear to be on a dome – cannot judge distance

Zodiac Constellations The plane of our solar system lies in these constellations The plane of our Galaxy is different Right now, for example, Saturn can be found in the constellation Leo

Sun Medium yellow star ~10 billion life span Primarily hydrogen with some helium Converts ~8 tons of matter per second to energy

Planets

April’s Planetary Show Jupiter rises in the east about 1 hour before the sun Saturn just after sunset in Leo’s lower left Mercury upper left just after the sun sets Mars in Cancer, high in the southern skies Venus – the brightest – is high in the south west sky after sunset

Mercury Only seen just after sunset or just before sunrise Smallest planet Most heavily cratered body

Venus Earth’s Twin (about the same size Hottest planet (runaway greenhouse gases) average 480ºC (850ºF) Sulfuric clouds Pressure ~ 100 feet under water

Mars About ¼ the size of Earth Not enough gravity to maintain a thicker atmosphere Average temperature is -61ºC (-81ºF) –Earth’s average is 15ºC (59ºF)

Jupiter Largest planet (1300 Earths would fit inside!!! 2.5x the gravity than on Earth Jupiter radiates more energy into space than it receives from the Sun

Jupiter’s Galilean Moons Developed by Barbara J. Shaw

Jupiter’s Galilean Moons

Size in Relationship to Jupiter

Size Compared to Earth

Night 1

Night 2

Night 3

Night 4

Night 5

Night 6

Night 7

Night 8

Night 9

Now you predict Night 10

Night 10

Can you place each moon in orbit around Jupiter?

Answer Io Europa Ganymead Callisto

Saturn Galileo described Saturn with ears Although all the gas giants have rings, only the Saturn rings are visible (but VERY thin ~30 feet!) Density of Saturn is so light, it would float in water

Uranus and Neptune

Asteroid Belt Between Mars and Jupiter Estimated 376,537 asteroids 1/1000th of the mass of the Earth

Kuiper Belt Beyond the orbit of Neptune (~30 to 55AU) Pluto/Charon and Eras are the largest bodies known in this region times more mass than Asteroid Belt 1.↑ The MPC Orbit (MPCORB) Database.↑The MPC Orbit (MPCORB) Database 2.↑ Carl D. Murray and Stanley F. Dermott (1999). Solar System Dynamics. Cambridge University Press. ISBN: ↑ 3.

Oort Cloud Outer reaches of our solar system from Kuiper Belt to ~50,000AU! Billions of comets

Moon Most familiar object in the sky Even preschoolers recognize pictures of the moon However, students struggle to explain the phases

Stopped by a cop He said, “Do you know how fast you are going?” I replied, “That, sir, is relative…”

How Fast? I was driving 55 miles per hour, but…

How Fast? The Earth, at the equator, rotating on it’s axis –1,040 miles per hour –In Portland, roughly 520 mile per hour

How Fast? The Earth revolving around the sun –67,000 miles per hour

How Fast? The Sun revolving around the Milky Way Galaxy –486,000 miles per hour

How Fast? The Milky Way Galaxy moving with the local cluster towards the constellation Hydra –1,340,000 miles per hour

How Fast? So, Officer, it is all relative, and 55 is insignificant! –I still got the ticket

Questions?