China is the only country to have successfully landed on the far side of Earth’s Moon.

Their Chang’e 4 mission has made history by touching down on the side of the moon that always faces away from Earth. On the lunar surface, the Chinese mission is exploring the landscape and taking images along the way.

As it explored the far side, going where no humans have ever been, the Chinese lunar mission has encountered something entirely unexpected: a strange “gel-like” substance inside one of the moon’s craters.

Curiosmos reported about the discovery not long ago, but since then, we’ve have not had any updates about the mystery substance.

Not, images of the alien material have finally been sent back to Earth, and we can finally see what the Chinese Yutu 2 rover found on the far side.

Thanks to the cameras onboard the Chinese rover, scientists on Earth can now have a better view of the odd material, thanks to a publication released last weekend by the Chinese-language science outreach publication Our Space, via their WeChat social account. Together with the images of the substance on the Moon, it is detailed how the Yutu-2 rover team approached the crater carefully despite the risk of the rover falling into it, and possibly getting stuck.

The scientists used the term “胶状物” (jiao zhuang wu), to describe the alien material the rover photographed, which can be translated as “gel-like.” The name of the odd material sparked interest and speculation among lunar scientists and UFO hunters.

Of the published image, the clearest one shows Yutu 2’s six wheels and the interior of a crater on the far side of the moon, estimated to be around 7 foot wide (2 meters). The black and white image was taken by the rover’s obstacle-avoidance camera. The green rectangular area and red circle marked within the crater are assumed to be linked to the field of view of the Visible and Near-Infrared Spectrometer (VNIS) instrument onboard the rover, rather than the alien material itself, according to some lunar scientists.

Although we can’t possibly know what the material is without sampling it, Clive Neal, a lunar scientist at the University of Notre Dame said in an interview with Space.com that while the image is not great, it provides clues to the nature of the material.

Neal indicates that the material in the center of the crater resembles the glass produced by the impact of a meteorite, such as that found during the Apollo 17 mission in 1972. High-speed impacts on the Moon’s surface melt and redistribute the rock within the circumference of the generated crater, sometimes creating rocks and crystalline structures.

Dan Moriarty, a scientist of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, thinks it is challenging to reach a definitive conclusion about the chemical composition of the substance found, especially because of the poor image quality. As explained by Moriarty, the material seems to be birther than the surrounding material, although the actual brightness of the gel-like material is hard to confirm from the poor images.

But although we can’t understand much from the image, Moriarty explained to Space.com that “Chang’e-4 landed in a mare basalt-filled crater, which is typically dark. Highlands crustal materials are typically brighter, so that would be a potential candidate.”

“It will be very interesting to see what the spectrometer sees, and if any higher-resolution images become available,” Moriarty revealed.