China’s Chang’e-4 lunar rover has discovered an unusually colored “gel-like” substance with a “mysterious lustre” on the far side of the Moon, researchers from the China Lunar Exploration Project have revealed.
Chang’e-4’s rover, Yutu-2, has been slowly pottering around the lesser-known side of the Moon since the mission's historic landing back in January. In nine months, the rover has covered a total of 271 meters (890 feet), exploring craters, while the lander has sent back spectacular – and of course, unprecedented – views from the far side of the Moon.
On July 28, three days after the start of lunar day 8 (lunar days last 29 Earth days, so Yutu-2 is experiencing two weeks of "day" and two weeks of "night"), Yutu-2 was about to be powered down for a “midday nap” to avoid overheating, as when the Sun is directly overhead, Moon surface temperatures can reach more than 100°C (212°F).
However, while surveying a panoramic of the crater the rover had just been exploring, something curious caught mission member Yu Tianyi’s eye. It was enough to postpone Yutu’s nap, and even postpone existing plans to travel west, instead rolling it back to the crater for a second look.
There, to the team’s surprise, they spotted what they have described as a gel with a mysterious lustre and a shape and color significantly different from the surrounding soil.
Yutu-2 has since scanned the crater using its Visible and Near-Infrared Spectrometer (VNIS), which detects light reflected off materials to get an understanding of their chemical make up, and though Chinese scientists haven’t revealed any more information about what they may have found (or released a photo), experts have weighed in at what they think this anomaly could be.
While undertaking this new and exciting detour, Yutu-2 traveled 1.96 meters (6.4 feet), breaking its own record for number of steps taken in a day: three! Don't laugh, that is the fastest it's ever moved, and leaves its predecessor, Yutu, in the dust at a paltry total of 114 meters (374 feet) after it short-circuited and became immobile just two months into its mission.
Yutu, meaning Jade Rabbit, is named after the pet belonging to the moon goddess Chang'e, in Chinese mythology. On January 3, 2019, Chang'e-4 completed the first-ever soft landing on the far side of the Moon, landing in the Von Kármán Crater in the southern hemisphere.
Since then, the mission has sprouted the first plant on the far side of the Moon, discovered lunar night is much colder than we had thought, and possibly discovered the first-ever sample of material originating from the Moon's mantle.
Both Chang'e-4 and Yutu-2 have just woken up for lunar day 9, and during this time Yutu-2 will continue its journey west (you can follow its "driving diary" here), where it will hopefully reveal more of the mysterious side of the Moon's secrets.