Solar SystemSolar System

Sun, Planets, Minor Planets, Asteroids, Comets, Meteors and

Lots of Space

http://apod.nasa.gov/apod/ap080206.html

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

http://apod.nasa.gov/apod/image/0710/Early-Bird-Special.jpg

December 4, 1997

Galaxies

• Large Magellanic Cloud

• Small Magellanic Cloud

• Andromeda Galaxy (found in the Constellation Andromda

http://domeofthesky.com/clicks/images/and.gif

Andromeda Galaxy2.2 million light years away

~13,200,000,000,000,000,000 miles13 quintillion miles

http://www.astro.uiuc.edu/~kaler/sow/andeep.jpg

Polaris

• Within 1º of our polar north

• Not always the “north star”

http://www.astropix.com/HTML/C_SPRING/URSAS.HTM

http://www.allthesky.com/various/umaumi.html

http://www.allthesky.com/various/umaumi.html

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

http://stardate.org/images/gallery/d_procession.jpg

Constellations

• Star patterns in sky• Acts like state lines in

a road map• Stars appear to be on a

dome – cannot judge distance

http://www.geocities.com/Heartland/Fields/8616/circumpolar.html

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

http://cse.ssl.berkeley.edu/IU/ISTAT/astross/activities/sky_coord2.gif

Sun

• Medium yellow star• ~10 billion life span• Primarily hydrogen

with some helium• Converts ~8 tons of

matter per second to energy

http://apod.nasa.gov/apod/ap030223.html http://apod.nasa.gov/apod/ap051005.html

Planets

http://apod.nasa.gov/apod/ap060828.html

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

http://apod.nasa.gov/apod/ap080319.html

Venus

• Earth’s Twin (about the same size

• Hottest planet (runaway greenhouse gases) average 480ºC (850ºF)

• Sulfuric clouds• Pressure ~ 100 feet

under water

http://apod.nasa.gov/apod/ap060110.html http://apod.nasa.gov/apod/ap050903.html

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)

http://apod.nasa.gov/apod/image/usgsmars.gif

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

http://apod.nasa.gov/apod/image/0212/jupiterIo_cassini_full.jpg

Jupiter’s Galilean Moons

Developed by Barbara J. Shaw http://photojournal.jpl.nasa.gov/catalog/PIA00343

Jupiter’s Galilean Moons

http://www.astro.psu.edu/users/niel/astro1/slideshows/class41/010-jupiter-galilean-moons.jpg

Size in Relationship to Jupiter

http://www.carinasoft.com/voyager4/info/images/ThreeMoonsOnJupiter.jpg

Size Compared to Earth

http://homepages.wmich.edu/%7Ekorista/ss-images/solarsys_compsizes.jpg

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Night 1

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Night 2

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Night 3

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Night 4

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Night 5

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Night 6

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Night 7

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Night 8

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Night 9

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Now you predict

Night 10

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Night 10

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Can you place each moon in orbit around Jupiter?

http://www.ox.ac.uk/images/maincolumn/257_Jupiter_from_Cassini.jpg

Answer

+2+1-1-2Io

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

http://apod.nasa.gov/apod/ap070407.htmlhttp://saturn.jpl.nasa.gov/multimedia/images/image-details.cfm?imageID=1398

Uranus and Neptune

http://hubblesite.org/gallery/album/entire_collection/pr2006047b/ http://apod.nasa.gov/apod/image/0406/nep2002_hst1pan_full.jpg

Asteroid Belt

• Between Mars and Jupiter

• Estimated 376,537 asteroids

• 1/1000th of the mass of the Earth

http://apod.nasa.gov/apod/ap040619.html

Kuiper Belt

• Beyond the orbit of Neptune (~30 to 55AU)

• Pluto/Charon and Eras are the largest bodies known in this region

• 20-200 times more mass than Asteroid Belt

1. ↑ The MPC Orbit (MPCORB) Database.2. ↑ Carl D. Murray and Stanley F. Dermott (1999). Solar System Dynamics. Cambridge University Press. ISBN: 0 521 57295.93. http://en.wikipedia.org/wiki/Image:Outersolarsystem_objectpositions_labels_comp.png#filelinks

Oort Cloud

• Outer reaches of our solar system from Kuiper Belt to ~50,000AU!

• Billions of comets

http://astro.berkeley.edu/~conor/ay250/pluto.html

Moon

• Most familiar object in the sky

• Even preschoolers recognize pictures of the moon

• However, students struggle to explain the phases

http://www.afreshhorizon.co.uk/moon_phases.htm

Stopped by a cop

• He said, “Do you know how fast you are going?”

• I replied, “That, sir, is relative…”

http://apod.nasa.gov/apod/image/0007/startrails_aat.jpg

How Fast?

• I was driving 55 miles per hour, but…

http://www.zenconsulting.net/jasonkehr/images/T1000.jpg

How Fast?

• The Earth, at the equator, rotating on it’s axis– 1,040 miles per hour

– In Portland, roughly 520 mile per hour

http://apod.nasa.gov/apod/image/0703/bluemarble_apollo17_big.jpg

How Fast?

• The Earth revolving around the sun– 67,000 miles per hour

http://www.ecology.com/archived-links/earths-orbit/index_files/earthorbit.gif

How Fast?

• The Sun revolving around the Milky Way Galaxy– 486,000 miles per hour

http://apod.nasa.gov/apod/ap011004.html

How Fast?

• The Milky Way Galaxy moving with the local cluster towards the constellation Hydra– 1,340,000 miles per

hour

http://apod.nasa.gov/apod/ap020123.html

How Fast?

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

http://www.rps.psu.edu/probing/graphics/light.jpg

Questions?

http://apod.nasa.gov/apod/image/etacarinae_hst.gif