China's lunar rover, Yutu-2, has discovered a strange "gel-like" substance on the far side of the Moon.
The substance, which is described as having "fascinating colours" and a "mysterious luster", was found at the bottom of a small, recent impact crater.
According to the Yutu-2 "drive diary" published by the government-sanctioned Chinese-language publication Our Space , the substance was "significantly different from the surrounding lunar soil".
China is yet to share images of the material, but it did share an image of the impact crater, captured by the rover.
One possible explanation, according to Space.com , is that the material is glass that was formed when a meteorite hit the surface of the moon and created the crater.
The Yutu-2 rover is part of China's Chang'e 4 mission - the first to explore the Moon's far side.
Since landing on the moon in January , Chang'e-4 and Yutu-2 have been conducting science and exploration tasks in and around the Von Kármán crater.
The crater is believed to be composed of various chemical compounds, including thorium, iron oxide, and titanium dioxide, which could provide clues about the origin of the lunar mantle.
Progress has been slow because both vehicles power down during lunar nights - a roughly 2-week period each month - when their location is in darkness.
The rover is also required to take intermittent "naps" - brief periods of hibernation - because of the daytime's brutal temperatures, which soar to 200 degrees centigrade.
Despite this, Chang’e 4's mission has already greatly exceeded expectations.
The rover and lander were only initially designed to last about three lunar days, (each lasting about two weeks), but it is now in its ninth lunar day.
It has covered a total of 890 feet (271 meters) so far, and will now continue its journey west.
