How do the atmospheres of the Moon and Mercury compare?
A) Mercury's is much denser, like Venus, with much carbon dioxide.
B) They are about equal, each only 1 as dense as ours.
C) The cooler Moon retains a thicker nitrogen atmosphere.
D) As no spacecraft has yet landed there, no information exists about Mercury's.
E) Neither body has a permanent true atmosphere.
Question 2
A fatal flaw with Ptolemy's model is its inability to predict the observed phases of:
A) the Sun during an eclipse.
B) the Moon in its monthly cycle.
C) Mercury and Venus.
D) Mars and Jupiter.
E) Jupiter and Saturn.
