Water, water everywhere—in our Solar System

Creating a new source of water, just because I can.

luc_viatour

Water ice is the most abundant solid material in the Universe. Much of it was created as the byproduct of star formation, but not all of it. John Bradley of Lawrence Livermore National Laboratory and his team may have discovered a new source of water in our solar system. His lab experiments reveal that the solar wind may be creating water on interplanetary dust.

The sun ejects high-speed charged particles in all directions. Bodies in the inner solar system get bombarded by this wind of particles, which continuously varies in intensity. Small bodies, such as dust particles or tiny asteroids, can be eroded by these harsh winds. Larger bodies that do not have an atmosphere, such as the Moon, are bombarded by both the solar wind and tiny meteorites. This form of bombardment causes a phenomenon called space weathering. (Atmospheres protect planets from tiny meteorites, while a magnetic field can deflect solar winds.)

The lunar dust brought back by the Apollo missions showed for the first time the result of space weathering—though not immediately. A careful examination of the dust returned from the lunar surface had to wait until the 1990s, when scientific instruments became good enough. When finally observed under sufficiently powerful microscopes, the dust particles revealed what have been called “rims.”