Scientists have found an unexplained, shiny gel on the far side of the Moon.
The mysterious substance was spotted by a Chinese lunar lander and it is unclear what the unusual thing could be.
As it was driving over the Moon's surface, Chinese lunar rover Yutu-2 spotted a strange shining object. It has examined the substance further but is yet to discover where the substance could have come from.
The Chinese space agency said that the discovery was made while the lunar lander was examining an impact creator, and described the object as being "a gel with a mysterious lustre lying in the centre of the crater". It had a shape and colour that was different from the soil around it, researchers said.
Some researchers have suggested that the shiny gel could be a glass that formed when the original impact event formed the creator. The heat of that collision could have created the glass that was spotted by the lander, they suggested.
But it remains yet to be explained and scientists will do more to find out where it came from, according to the Chinese space agency.
The discovery began at the end of July, when engineers that control the Yutu-2 lander were beginning to power it down ahead of one of its regular naps. The lander has to shut down throughout the day because its parts could be damaged by the heat of the Sun when it comes directly overhead.
As that was happening, one of the team members spotted something strange in one of the panoramic photographs sent back by Yutu-2. They postponed the rover's nap and instead drove it to the crater to examine it.
It was there that they found that it was a shining substance that stood out from the soil around it. Despite further scans of the object, researchers were unable to find what it might be.
