The American space survey Messenger has confirmed the existence of water ice in deep craters at the north pole of Mercury.
"It must be the last thing you might expect from the nearest planet to the sun - is water ice. But due to the low inclination of Mercury craters near the poles are in the shade all year, and there is extremely cold, "- explained Matthew Sigler's Jet Propulsion Laboratory NASA.
A team of astronomers studied data from neutron spectrometer Messenger, craters Kandinsky and Prokofiev. And it turned out that the bottom of each of them consists of two layers.
A crater on the surface is a thin crust, a depth of 15-20 cm, made of a mixture of soil and Mercurian complex organic molecules. The proportion of water in them is quite low - not more than 25%. The second layer, whose thickness exceeds the penetration of the spectrometer, is almost entirely composed of water.
According to calculations of scientists, the craters of Mercury may contain from 20 billion to 2 trillion tons of water.
Scientists believe this level of ice could be brought to Mercury by comets and meteorites in the early ages of life Solar System.
First hypothesis of ice deposits on Mercury was made decades ago. The idea was developed in 1991 when a radio telescope Arecibo Observatory (Puerto Rico) issued radar images with bright spots at the poles of Mercury. A probe data Messenger, received last year and this year, confirmed that all the bright spots on the north and south poles are in shady areas. This has been agreed with the hypothesis of water ice.
Latest discovery will help astronomer’s better find water supplies and other airless celestial bodies. The immediate goal for such studies can serve as the asteroid Ceres, which Dawn probe reaches out in February 2015.