MadSci Network: Earth Sciences
Query:

Re: How did water get on the Earth?

Date: Fri Sep 11 17:46:02 1998
Posted By: Aaron Romanowsky, grad student,Harvard-Smithsonian Center for Astrophysics
Area of science: Earth Sciences
ID: 905126315.Es
Message:

Good question! The answer is -- by rain from the Earth's atmosphere. This brings up the next question -- how did the atmosphere get here?

We have good reason to believe that the Earth's original atmosphere (left over from the Earth's formation process) was about a thousand times sparser than it is today. So our current atmosphere must have come from volcanic gases, originating in the Earth's interior. Measurements of the gas coming from volcanoes today (on Hawaii, for example) have found that it is mostly composed of water vapor and carbon dioxide. Voila, the oceans! (with vast amounts of carbon dioxide locked up in them)

A recent twist on this scenario is a very controversial theory that the Earth is being bombarded continually be millions of mini-comets (house-sized) per year. As they are composed mostly of water-ice, these comets would deposit a large amount of water on the Earth over long periods of time. For more info, see this page.

-Aaron


Current Queue | Current Queue for Earth Sciences | Earth Sciences archives

Try the links in the MadSci Library for more information on Earth Sciences.



MadSci Home | Information | Search | Random Knowledge Generator | MadSci Archives | Mad Library | MAD Labs | MAD FAQs | Ask a ? | Join Us! | Help Support MadSci


MadSci Network, webadmin@www.madsci.org
© 1995-1998. All rights reserved.