First on-site evidence of water on Moon

Chang’e 5 lunar lander of China has found first-ever on-site evidence of water on the surface of moon.

Highlights

• Study was published in the peer-reviewed journal Science Advances on January 8, 2022.
• It revealed that the lunar soil at the landing site comprises of less than 120 grams water per ton or120 parts-per-million (ppm) water.
• It further reveals that, a light, vesicular rock carries 180 ppm water.
• These are much drier as compared to that of Earth.

Confirmation of Water

Presence of water on Moon had been confirmed by remote observation earlier. However, lander has detected signs of water in rocks and soil.

How was water detected?

• Water was detected on the spot for the first time, by a device on-board the lunar lander. The device measured the spectral reflectance of regolith and rock.
• Water content in the regolith and rock can be estimated since water molecule or hydroxyl absorbs at a frequency of around three micrometers.

What contributed to humidity of lunar soil?

According to researchers, Solar wind contributed to the most humidity of lunar soil. Solar wind brought hydrogen, which makes up the water. While, additional 60 ppm water in the rock is believed to be originated from the lunar interior.

The Chang’e-5 spacecraft

It is the fifth lunar exploration mission of Chinese Lunar Exploration Program. It is also the first lunar sample-return mission of China. It has been named after the Chinese moon goddess Chang’e. The space craft was launched on November 23, 2020 from Hainan Island and it landed on the Moon on December 1, 2020. It collected around 1,731 g of lunar samples and returned to the Earth on December 16, 2020. The spacecraft had landed on one of the youngest mare basalts, which is located at a mid-high latitude on the moon.

What samples did it collect?

The spacecraft collected the samples, which are a mixture of granules. It was collected from both on the surface and beneath.