Based on Mercury's peak temperature of about 700 K, what would the average molecular speed of carbon dioxide be? How does this compare to Mercury's escape velocity? If Mercury's atmosphere initially had substantial carbon dioxide, in line with what
is believed about the early atmospheres of the other terrestrial planets, do you think Mercury would have retained this atmosphere? Why/why not? Would your answer change if you considered only Mercury's coldest regions that are around 125 K?
Question 2
Interstellar gas is composed of:
A) only hydrogen.
B) 90 hydrogen, 9 helium by weight.
C) 10 hydrogen, 90 helium by numbers of atoms.
D) some hydrogen, but mainly carbon dioxide.
E) ammonia, methane, and water vapor.