"Water appears to be one of the most abundant molecules in the Universe. It dominates the environment of the Earth and is a main constituent of numerous planets, moons and comets. On a far greater scale, it possibly contributes to the so-called 'missing mass' [i.e., dark matter] of the Universe and may initiate the birth of stars inside the giant molecular clouds."
From Alex Daley, Chief Technology Investment Strategist, Casey Research:
Water is not scarce. It is made up of the first- and third-most common elements in the universe, and the two readily react to form a highly stable compound that maintains its integrity even at temperature extremes.
Hydrologist Dr. Vincent Kotwicki, in his paper "Water in the Universe," writes:
Oxygen has been found in the newly discovered "cooling flows" – heavy rains of gas that appear to be falling into galaxies from the space once thought empty surrounding them, giving rise to yet more water.
How much is out there? No one can even take a guess, since no one knows the composition of the dark matter that makes up as much as 90% of the mass of the universe. If comets, which are mostly ice, are a large constituent of dark matter, then, as Dr. Kotwicki writes, "the remote uncharted (albeit mostly frozen) oceans are truly unimaginably big."
Back home, Earth is often referred to as the "water planet," and it certainly looks that way from space. H2O covers about 70% of the surface of the globe. It makes all life as we know it possible.
However it got here – theories abound from outgassing of volcanic eruptions to deposits by passing comets and ancient crossed orbits – water is what gives our planet its lovely, unique blue tint, and there appears to be quite a lot of it.
That old axiom that the earth is 75% water... not quite. In reality...
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