In a book Impact Earth: Asteroids, Comets and Meteoroids: The Growing Threat by Austen Atkinson, I seem to remember reading that we get a regular rain of ice here on earth from comet dust and space debris. Unfortunately, the book does not have a very good Index so I couldn’t find the info. on how many tons a year are added to our water supply.
Comet’s water ‘like that of Earth’s oceans’
BBC | October 5, 2011 | Jason Palmer
Posted on 10/05/2011 6:41:44 PM PDT by decimon
http://www.freerepublic.com/focus/news/2788555/posts