Astronomy 100

Comparative PlanetologyMercury, Venus, Earth, Moon, Mars

• Now: How are planets formed? Why does Earth have water? How do rocks form?

• Main concepts: solar system formation, comparative planetology, Moon formation hypotheses, cratering, plate tectonics, volcanism, earthquakes, atmosphere, solar wind/auroras,

• Vocabulary: protoplanetary disk, crater, Heavy Bombardment, cratering, atmosphere, mantle, differentiation, plastic, greenhouse effect, albedo, ejecta, rays, solar wind, auroras

Formation of the Solar System• The Solar Nebula was spinning

– Protostar– Protoplanetary disk

• Bits coalesced• Ta-da – planets!• NOW:

– String represents 5 billion years (50 feet)– Each foot is 100 million years.– Place the events in order.– You have 20 minutes ONLY

• Heavy Bombardment

• Differentiation

• http://www.youtube.com/watch?v=Ss1FNrNTGRM

Robert Simpson http://farm4.static.flickr.com/3160/2946389087_57dfbb682e_b.jpg

• Crust• Mantle• Core

• Plastic

From: NASA http://www.nasa.gov/worldbook/wbkids/k_earth_prt.htm

Fission, Capture, Condensation, Giant Impact?

Starchild/NASA http://starchild.gsfc.nasa.gov/docs/StarChild/questions/question38.html

Crater, ejecta, rays, albedo

NASA http://craters.gsfc.nasa.gov/crater_diagram.html

http://messenger.jhuapl.edu/

Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

http://messenger.jhuapl.edu/

Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

http://messenger.jhuapl.edu/

Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

• Comparative Volcanoes

Volcanoes• Composite• Shield

http://mars.jpl.nasa.gov/gallery/atlas/images/oly-az.jpghttp://svs.gsfc.nasa.gov/stories/Landsat_USCities/images/mt_rainier_natural.jpg

Plate Tectonics

http://marsweb.jpl.nasa.gov/mgs/mission/images/PIA02820_mola.jpg

• Martian North Pole and Terrestrial (Earth) South Pole– Describe three things that are the same about the landforms. – Describe three things that are different about the landforms. – Why do both planets have ice caps? – Why are the ice caps different sizes?

• Valles Majas & the Grand Canyon– Describe three things that are the same about the landforms. – Describe three things that are different about the landforms. – What force do you think formed the Grand Canyon? – What force do you think formed Valles Majas? – Do you think it is the same force? Why or why not? How do your

observations support this conclusion?• Olympus Mons and the Hawai’ian Islands

– Using the contour gauge, trace the profile of both Olympus Mons and Hawai’i. Draw your guess for what the internal structure might look like inside both volcanoes.

• Weathering/Protection– Water– Atmosphere

• Greenhouse effect• Solar wind

• Answer Now:

• Why do the Moon and Mercury have more craters than the Earth?

• What types of planets are there in our Solar System?

• Now: How many other worlds have humans walked on? How many “planets” have we “explored?”

• Main concepts: – Mercury missions past and future– Venus missions past and future– Moon missions past and future– Mars missions past and future

• Vocabulary: Apollo, MER, Altair, Constellation, Venera, MESSENGER

• Answer Now:

• Why do the Moon and Mercury have more craters than the Earth?

• What types of planets are there in our Solar System?