Asteroids and Water

Water is essential to human life – as our bodies consist for about 60 percent of it – and finding a suitable and abundant source of water is crucial for the establishment and survival for orbital space settlements. Fortunately water is composed from two of the three most common elements in the Universe: hydrogen and oxygen.

ScienceDaily reports that two researchers from the University of Arizona have discovered pyroxene in samples collected from the asteroid Itokawa by a Japanese mission. Pyroxenes are minerals that often contain water as part of their structure. Because the water is part of the mineral, it is protected from evaporation as water ice would.

The two chemists found that the amount of water in these samples was higher than was expected. Itokawa is a so-called S-type asteroid, with the S of stony. S-type asteroids are among the most common asteroids and if this result is typical for other siliceous asteroids, than future space settlers do not need to worry about finding a water source.

Itokawa is, however, not the only asteroid with substantial water reserves. Another ScienceDaily reports states that scientists have found evidence of water-bearing minerals on Bennu, a carbonaceous near earth asteroid, using data collected by NASA.

As an interesting side note, according to the first study about half of all water here on Earth might be derived from asteroid impacts.