What is one hypothesis for why the crust in the northern hemisphere of Mars is thinner and lower than that in the southern hemisphere?
A) a giant impact blasted away crust from the northern hemisphere
B) it once hosted an ocean of water which eroded away the crust
C) tectonic activity caused the southern hemisphere to rise up above the level of the northern hemisphere
D) massive marsquakes caused the northern hemisphere to subside
Question 2
Suppose it is January and the Sun remains above your horizon all day long. Where must you be located?
A) at the South Pole
B) at the North Pole
C) somewhere between the Antarctic Circle and the South Pole
D) somewhere between the Arctic Circle and the North Pole
Volcanic plateaus (red) and impact basins (blue) dominate this topographic map of Mars
Animation of the apparent retrograde motion of Mars in 2003 as seen from Earth
Psoriasis, lower extremities
The respiratory system. (a) Sagittal section of the head and neck, revealing the organs of the upper
Muscles of the posterior lower leg.
Pitting edema of the lower extremities