Chapter 3: Q18-29DQ (page 610)
The dark areas on the moon鈥檚 surface are called maria, Latin for 鈥渟eas,鈥 and were once thought to be bodies of water. In fact, the maria are not 鈥渟eas鈥 at all, but plains of solidified lava. Given that there is no atmosphere on the moon, how can you explain the absence of liquid water on the moon鈥檚 surface?
Short Answer
All the water has vaporized, and thus, no liquid exists on the moon鈥檚 surface.