Sentences with phrase «later by comets»

Early moon geology recreated in the lab suggests water was there to begin with, not added later by comets

Not exact matches

This is no time for a child to be born, With the earth betrayed by war & hate And a comet slashing the sky to warn That time runs out & the sun burns late.

Amy Barr and Robin Canup of the Southwest Research Institute in Boulder, Colorado, think they know why: the moons were pummelled to differing degrees by wayward comets during the «late heavy bombardment», a cataclysmic period that began 3.9 billion years ago.

Those results set the age boundary for the oldest terrains on Mercury to be contemporary with the so - called Late Heavy Bombardment (LHB), a period of intense asteroid and comet impacts recorded in lunar and asteroidal rocks and by the numerous craters on the Moon, Earth, and Mars, as well as Mercury.

That led many scientists to suggest that water would have been introduced on Earth at a later time, when it was pummeled by comets and asteroids during the Late Heavy Bombardment period, 4.1 to 3.8 billion years ago.