The *big* picture (part 2)

In "The *big* picture (part 1)" we reviewed astronomical news of Mercury, Venus, Earth, and (some) asteroids. Today we'll start with Mars and head on out ...

Beginning with the possibility that maybe Mars isn't as dry as it has seemed. Indeed, perhaps "Parts of Mars's interior are as wet as Earth's." Studies of meteors of Martian origin indicate that:

... the mantle from which the meteorites derived contained between 70 and 300 parts per million (ppm) of water. Earth's mantle,  for compari...