| 单词 | late heavy bombardment |
| 释义 | > as lemmaslate heavy bombardment late heavy bombardment n. (also with capital initials) Astronomy an event suggested as having occurred during the early history of the solar system, when an exceptionally large number of asteroids may have collided with the terrestrial planets as they were being formed.This event is dated to about 4 billion years ago, a time late in the accretion period of the solar system (though not in the history of the solar system as a whole). ΚΠ 1975 G. W. Wetherill in Proc. 6th Lunar Sci. Conf. II. 1540 In addition to the ‘early heavy bombardment’ which more or less accompanied the accretion of the planets, there was thus a ‘late heavy bombardment’ which continued for hundreds of millions of years. 1989 Nature 12 Oct. 514/1 The Noachian martian valleys probably formed before the end of late heavy bombardment. 2008 N.Y. Times (National ed.) 2 Dec. d1/2 Scars on the surface of the Moon record a hail of impacts during what is called the Late Heavy Bombardment. < as lemmas |
| 随便看 |
英语词典包含1132095条英英释义在线翻译词条，基本涵盖了全部常用单词的英英翻译及用法，是英语学习的有利工具。