Astronomy 150 - Exam #1 Name:October 24, 1997 TA’s Name & Section (2 pts):Answer all questions in the space provided. Please write in complete sentences.If you have any questions raise your hand. 100 points possible.1 (5 pts) Apollo 15 landed next to Hadley Rille (a sinuous rille). Describe how this featurewas formed and what types of rocks would you expect to find in Hadley Rille.2 (5 pts) I said in class that the surface of Mercury and the Lunar highlands are about thesame age because they have about the same crater density. Explain why this assumptionmay not be correct.3 (3 pts) How would you find the absolute age of the surface of Mercury?You have discovered an airless planet orbiting between the Earth and Mars. You measureits compressed density to be ρ = 6 gm/cm3and its uncompressed density to beρ = 4 gm/cm3.4 (3 pts) Describe the approximate composition of this planet.5 (4 pts) Is this world larger or smaller than Mars? Explain your answer.6 (5 pts) If you were to half the size of the Earth (shrink its radius by a factor of two) anddouble the mass of the Earth, how much would it change the gravity on the Earth (howmuch would your weight change)? [show your work]7 (10 pts) All of the worlds we have studied so far have impact craters. Pick one world(Mercury, Venus, or Mars) and describe two ways the impact craters on that world differfrom impact craters on the Moon.10 20 30 40 50GasSolidLiquid12453Temperature (C)Pressure (atm)This is the phase diagram for a substancecalled Oobleck. Use it to answer the followingthree questions.8 (2 pts) If the temperature in this roomwere 10 C what phase would Oobleck be in?(check one) Solid Liquid Gas9 (5 pts) If I were to raise the temperature in this room slowly from 10 C to 55 C describewhat would happen to the Oobleck.10 (5 pts) If I were to increase the air pressure in this room to 4 times its normal value andthen increase the room temperature slowly from 10 C to 55 C describe what would happento the Oobleck.This is an image of a thin–section of a Lunar samplewe saw in class. Use it to answer the next four questions11 (4 pts) What type of sample is this? (checkone) Mare Basalt Impact Breccia Lunar Regolith Plutonic Rock Orange Soil12 (4 pts) What are the characteristics of the thin–section that you used to answer the abovequestion?13 (5 pts) Describe how this sample was formed.14 (5 pts) Where on the Moon would you expect to find this sample?15 (3 pts) Explain what it means for a planetary body to be differentiated.16 (10 pts) One to the constraints on the theory of the origin of the Moon is that it hasto account for the fact that at one time a large portion of the outer layer of the Moon wasmolten. Explain why the existence of low density Plutonic rocks (plagioclase feldspar) makesus think the Moon once had a “Magma Ocean”.Below is a geological map of a planetary surface. Use it to answer the next three questions.ABCED17 (5 pts) Indicate the relative agesof the various landforms from oldest -formed first (1) to youngest - formed last(5).A - Lava FlowB - Cratered TerrainC - Sinuous RilleD - Straight RilleE - Crater and Ejecta18 (5 pts) If you were to land on this surface at the point marked by the letter “B”, whattypes of rocks would you find there?19 (10 pts) You are in charge of planning a mission to this site. You have twoconstraints: 1) You can only explore a limited area (equivalent 1 in2on the map,the box on the left is 1 in2) and 2) You can not cross either rille (C or D). Placean “X” on the map where you would land and explain why you chose this