CNSA/CLEP

During its last lunar day of exploration, China's moon rover, Yutu-2, stumbled upon a strange, "gel-like" substance in the middle of a crater. Chinese lunar scientists were perplexed but there were suggestions the material was created by a meteor impact which caused melt glass to be left behind. Soon after the discovery, China put Yutu-2 to work as a Sherlock Holmes, ready to solve the case of the weird moon muck.

In a recent social media update, picked up by Space.com's Andrew Jones, Chinese scientists detail their mission to the crater to study the strange substance. Unfortunately, a comprehensive understanding of the unusual substance remained elusive during a first pass, as the 2-meter-wide crater was draped in shadow.

On Yutu-2's last exploration day (a 14-day cycle on the moon), it again examined the site -- this time with a little more dare.

CNSA/CLEP

On second approach, Yutu-2 got closer to the crater to give the scientists the best chance at making a detection with the on-board spectrometer. The risky maneuver was hotly debated by the science and driver teams, according to the social media update, but in the end it seems to have paid off. A piece of the material was detected, but lunar program scientists are yet to reveal what exactly they found.

The surface of the far side of the moon has remained out of reach for human explorers, but Yutu-2 has been doing a bang-up job of providing Earthlings with excellent panoramas of the desolate plains. The rover, the first to explore the moon's far side, touched down on the lunar surface in January and will continue to explore, with its 10th day of exploration beginning Sunday, Sept. 22, and lasting for the next two weeks.