The Solar System – ASTR 121

Second Midterm – February 17, 2016, 09:00-09:50

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, labeled diagrams, and formulas with symbols defined, where appropriate.  Each question is worth two points.

A.  Briefly describe two major features of the solar system that provide clues to how it was formed.

B.  What do we mean by the solar nebula?

C.  Why did the jovian planets end up with many moons?

D.  What was the heavy bombardment, and when did it occur?

E.  What is a half-life (of a radioactive element)?

F.  Why are extrasolar planets hard to detect directly?

G.  Why does Earth have a global magnetic field?

H.  How are Mercury's great cliffs (scarps) thought to have formed?

I.  What might explain the lack of plate tectonics on Venus?

J.  Choose a geographical feature on the surface of Mars.  Explain its nature and likely origin.