How were the smooth,dark plains called maria formed on the Moon's surface?
A) They were formed by tidal interactions with the Earth very early on in its history.
B) The maria are ancient sites of gigantic impact craters and have smoothed over time.
C) They were formed from lava flows that covered old,cratered lowlands.
D) The maria formed where solar flares touched the surface of the Moon and scarred it.

Question

Quizplus · Accepted Answer

The maria on the Moon were formed by ancient volcanic activity. Lava flowed out and filled large basins, creating the smooth, dark plains we see today.

How Were the Smooth,dark Plains Called Maria Formed on the Moon's