Review 1 Astronomy 150, April 25 th 2005

Phase diagrams Phase diagrams – describe state of a material How cold would you have to make this room so that CO 2 would be solid? –Decrease temperature below -78 degrees Celzius How would you change the conditions of this room so that CO 2 could exist as a liquid? –Increase pressure above 5.1 atm and temperature between and -31 C

Vocabulary Densities –Water (ice) = 1 g / cm 3 –Rocks = 3 g / cm 3 –Iron = 8 g / cm 3 Mercury  5.4 g / cm 3 –Rocks and iron Jupiter  1.3 g / cm 3 –NOT made of ice! Moment of inertia factor K –Uniform sphere  K = 0.4 –Mass more concentrated in the center  K < 0.4  planet is differentiated

The Moon

Regions: a)Mare b)Highlands Mare –Albedo: low –Age: young (How do we measure age?) –Crater density: low –Main feature: lava flows –Primary rock type: basalt (low albedo) Highlands –Albedo: high –Age: old –Crater density: high –Main feature: impact craters –Primary rock type: impact breccias, highland pristine rocks

The Moon Impact processes: –Simple impact craters –Complex impact craters  mounds  how do they form? –Impact basins  when were they formed?

The Moon

Rocks