China’s Chang’e 5 Lunar Probe
China’s Chang’e 5 lunar lander has found the first-ever on-site evidence of water on the surface of the moon, lending new evidence to the dryness of the satellite.
- The study published in the peer-reviewed journal Science Advances revealed that the lunar soil at the landing site contains less than 120 parts-per-million (ppm) water or 120 grams water per ton, and a light, vesicular rock carries 180 ppm, which are much drier than that on Earth.
- The presence of water had been confirmed by remote observation but the lander has now detected signs of water in rocks and soil.
- A device on-board the lunar lander measured the spectral reflectance of the regolith and the rock and detected water on the spot for the first time.
- The water content can be estimated since the water molecule or hydroxyl absorbs at a frequency of about three micrometers.
- According to the researchers it was the solar wind that contributed to the most humidity of lunar soil as it brought hydrogen that makes up the water.
- The study revealed that the moon had turned drier within a certain period, owing probably to the degassing of its mantle reservoir.
Source : Indian Express