Water from Spacegreenspun.com : LUSENET : Introductory Geology, Oswego State : One Thread
How is it that water from outer space enters the Earth? Is there any differences or other elements in that water?
-- Ellen Hanley (firstname.lastname@example.org), April 23, 2001
ok, I'm pretty positive that water does enter the earth from outer space. Water has always been on earth, and is transferred to the atmosphere by evaporation from the oceans, by evaporation and transpiration from the continents, and by sublimination from glaciers...aka The Hydrologic Cycle....no space involved.....but, to answer your question on space water, I found a site that dealt with this issue:
Yes, there is quite a lot of water in space, but it does not exist in the vacuum of space as a liquid. Water can only exist in space in two forms:
(a) As a gas - steam if you like.
(b) As a solid - ice.
The reason why water canít exist as a liquid is because the pressure of the earthís atmosphere (air) stops water from boiling. When you remove the pressure of air - as in space - water will boil at the same temperature as it freezes! (0 degrees Celcius). As you reduce the air pressure water boils at lower and lower temperatures. By the time you have reduced the air pressure to 7/1000thís of normal air pressure boiling and freezing temperatures are the same for water. Sometimes people climbing very high mountains find it hard to make a nice hot cup of tea or cook food properly because the air pressure is so low that water boils before it is hot enough to cook food or make tea properly. In space there is no air at all so that means that you will never find liquid water. Also the temperature in space, away from the Sun or a star will be very low; typically -250 to -265 degrees C! At this temperature, in the almost perfect vacuum of space steam can exist (as a gas), but it would like to turn into ice if it could. In space, between the stars, there are quite large quantities of very tiny dust grains, these come from old stars. The dust grains are made up of such elements as Carbon (the basic element in living things), Silicon (the basis of rocks), Iron, Manganese, Aluminium, Sulphur, etc., etc. At the very low temperatures in space the water molecules tend to freeze out as a coating on these grains. This means that we find that the very thin clouds of gas between the stars usually contain dust grains coated with ice.
-- Joel Bouchard (email@example.com), April 27, 2001.
According to this article i was reading online, scientist didn't first find water on an object come to earth from space until 1999. Even that was not even enough to see on the head of a needle. The article did say however that the water provided clues to the "solar nebuela." Try these two sites: www.iso.vilspa.esa.es/sciences/as_dis_wat.html and http://west.pima.edu/~geology/waterinmeteor.html
-- Deb Richards (firstname.lastname@example.org), May 03, 2001.
i dont know but i need to know what prevents water from evaporating into outer space
-- n/a (email@example.com), December 11, 2002.