The Solar System – ASTR 121
Second Midterm – November 2, 2012, 9:00-9:50
Instructions: Print your name and student identification number at the top of this page. Answer each of the questions A through J in the space provided. Be clear and thorough in your answers using sentences, sketches, and formulas where appropriate. Each question is worth two points.
A. What is Rayleigh scattering, and what is a noticeable effect of it for us on Earth?
B. Give two reasons for thinking the Earth's core is liquid.
C. What is a synchronous orbit, and how did the orbit of the Moon come to be this way?
D. What is a scarp and how are they thought to have formed on Mercury?
E. Give two pieces of evidence for active volcanoes on Venus.
F. What are the two main constituents of Venus's atmosphere?
G. Give two pieces of evidence that Mars never melted as extensively as the Earth.
H. What is the evidence Mars once had an extensive ocean? Where was it?
I. What is convection, and how does it affect the Earth's atmosphere?
J. The Moon has a radius of about 1/4 of Earth's and a mass of about 1/80 Earth's. Calculate the density of the Moon relative to the Earth from these numbers.