Question 1
How did the lunar maria most likely originate?
◦ Huge impact basins were nearly filled with basaltic lava flows.
◦ The solar wind eroded very wide, shallow basins that filled with lunar dust.
◦ Huge impact craters filled with frozen carbon dioxide and dark-colored silt and dust.
◦ Massive, basaltic comets melted when they hit the lunar surface.
Question 2
Why do lunar scientists think the surface of the Moon was once a magma ocean?
◦ The surface of the Moon is entirely volcanic.
◦ Early lunar craters show a morphology suggesting impact with a liquid.
◦ The lunar highlands contain large amounts of the rock anorthosite, which is the light material that "floated" on the top of the magma ocean.
◦ None of these is correct.