Chapter 11

What is the reason that the northern plains of Mars have a much smaller crater density than the cratered terrain of the southern hemisphere?

The Earth is closest to the Sun in January, which is summer in the southern hemisphere. Why isn't the difference between northern and southern seasonal variations as extreme on the Earth as on Mars? (You should give an astronomical reason, which is part of the full explanation.)

What is the reason that the Martian surface and sky are somewhat pink?

What is the connection between Martian wind patterns and the variable dark surface markings seen from the Earth?

Mars has nearly the same rotation period as the Earth, yet Mars has no detectable global magnetic field. What possible difference between the two planets could account for the absence of a Martian magnetic field?

In what kinds of places is water observed to exist or believed to exist on Mars today?

What evidence do we have that Mars was once much wetter and hotter than it is today?

What evidence of water on Mars was found by the Opportunity rover?