A Lunar Chronology

被引：0

作者：

Schaeffer, Oliver A.

机构：

来源：

Bulletin of the Atomic Scientists | 1973年 / 29卷 / 10期

关键词：

Moon;

D O I：

10.1080/00963402.1973.11455543

中图分类号：

P144 [恒星物理学];

学科分类号：

摘要：

The Moon was formed either at the same time as the Earth or only a short time later, about 4.6 billion years ago. After formation, there was a period of intense bombardment of the lunar surface by objects of asteroidal size. They formed the large basins now filled with mare basalts. It is not at present clear whether these impacts occurred in a series in time or in a group at about the same time. It does seem clear that there was a significant change in the bombardment rate 3.9 to 4 billion years ago. The author is professor of geochemistry in the Department of Earth and Space Sciences, State University of New York, Stony Brook, N. Y. © 1973 Bulletin of The Atomic Scientists.

引用

页码：42 / 45