How large were the impactors that created the craters that in turn became the large maria?

Question

Quizplus · Accepted Answer

The impactors that created the large maria on the Moon were at least 100 kilometers or more in diameter. This is because the size of the crater is directly related to the size of the impactor that created it. The largest and most well-known maria on the Moon, such as Mare Imbrium and Mare Serenitatis, were formed by impactors that were over 100 kilometers in diameter.

How Large Were the Impactors That Created the Craters That