The mysterious green "gel-like" substance found on the moon last year has been identified. Sadly, it is not the drool from a Xenomorph alien or some kind of ancient extraterrestrial treasure. Chinese scientists have published an analysis of the substance, which was discovered by the Yutu 2 rover last year on the far side of the moon. When they previously announced their findings, people began to speculate about what it could possibly be, with some imaginations running wild.
China's Change's 4 mission focuses on studying the far side of the moon with its Yutu 2 rover. As of December 2019, the rover holds the record for longest working rover on the moon and it's still up exploring right now. Scientist Yu Tianyi was the first to notice the substance, which "was a dark greenish color and glistened." Scientists actually rerouted the rover in order to explore further due to the size of the substance. The gel sample patch they took measures 20 inches by 6 inches and it, "resembles impact melt breccia, a type of rock that forms through an impact event, [and] samples returned from the Apollo missions."
The gel-like material was found in the Von Kármán crater, which is a massive impact crater on the far side of the moon. The "breccia - broken fragment of minerals cemented together - was formed by impact-generated welding, cementing and agglutinating of lunar regolith and breccia." The main component in the sample is "plagioclase, which is a major constituent in both Earth and the moon's crust. It also contained iron-magnesium silicate minerals olivine and pyroxene." It also contains samples from other craters on the moon, meaning that whatever meteor that made the impact ejected debris from the area and spread it out. So, this is pretty much melted bits of moon rock.
While it sounds like they have it all figured out, NASA has revealed that they really aren't 100% certain. "We don't have samples from this region that would help inform the model parameters," NASA's Dan Moriarty says. "For this reason, the precise regolith composition results presented in this paper may not be completely accurate." While they can't say for certain, it is still not anything from aliens. It's basically a fancy moon rock that could be the result of a meteor strike or volcanic eruptions, though scientists have pretty much ruled out eruptions since it's been over 3 billion years since there was volcanic activity in the area.
Even though the gel-like substance isn't gel or even anything from aliens, it's still interesting to see that even the world's best scientists are still studying the moon and finding new things. Many wanted the green material to be from Martians, but it seems to be a naturally occurring element, thanks to a meteor crashing down on the moon. For now, Yutu 2 is still exploring the moon and looking for more things to investigate and explore. The news was originally reported by Space.com.