Yutu 2 Reveals Possible Causes of Unknown Gelatinous Substance on Moon

Yutu-2 lunar rover near an impact crater. (Credit: China National Space Administration)

BEIJING (China National Space Administration PR) — Since landing on the back of the moon, the Chang’e 4 lander and the Yutu-2 lunar rover have been operating successfully for more than 500 days, and have achieved many results in the scientific fields such as the material composition and underground structure of the landing zone.

During the eighth day of the month, the Yutu 2 lunar rover found an unknown substance with a size of about 52 cm x 16 cm inside a fresh impact crater with a diameter of about 2 m and a depth of about 0.3m. Compared with the surrounding lunar soil, the unknown substance has an irregular shape, showing a black-green color with a certain luster. 

In response, the flight control team of the Beijing Aerospace Flight Control Center has formulated a strict driving plan and conducted detailed scientific detection of fresh impact craters and unknown substances.

Panoramic image mosaic of the surrounding environment of unknown substances inside the fresh impact pit. (Credit: China National Space Administration)

Recently, Dr. Qian Sheng, State Key Laboratory of Remote Sensing Science, Institute of Information Innovation, Chinese Academy of Sciences, member of the Center for Excellence in Comparative Planetary Innovation, Chinese Academy of Sciences and Pilot Project Leader, State Key Laboratory of Remote Sensing Science, Institute of Information Innovation, Chinese Academy of Sciences Researcher Shidi Kaichang, Researcher Yue Zongyu, and their collaborators used the detection data of “Yutu No. 2” to analyze the cause of the “unknown gelatinous substance”.

Obstacle avoidance camera images acquired by the Yutu-2 lunar rover. (Credit: China National Space Administration)

The scientific research team found that there are many gray blocks similar to the lunar soil around the fresh impact crater. They can be crushed into powder by the wheels of the lunar rover, inferring that they are massive moon soil, not stones. 

Spectral unmixing results show that the relative content of feldspar minerals in the massive lunar soil around and inside the fresh impact crater is relatively large, and the relative content of olivine and pyroxene is basically equal, indicating that the lunar soil in the landing area may be the weathering product of sulvinite.

Compared with the samples collected by the Apollo mission, the appearance of the unknown material and the breccia samples are similar. After further theoretical analysis of impact crater formation, the unknown substance is breccia formed by impact, which may be the impact molten breccia from the sputter of a nearby impact crater, or the impact glass condensation formed when the current fresh impact crater is formed. Breccia.

At present, the Chang’e 4 lander and the Yutu-2 lunar rover are in the nineteenth day working period. The two devices are in normal working conditions and have balanced energy. They carry out scientific exploration missions as planned. 

In the follow-up, the scientific research team will continue to scientifically plan the detection missions of the Chang’e 4 lander and the Yutu-2 lunar rover, and will operate closely to obtain more first-hand detection data on the back of the moon, in-depth research and analysis, and related scientific achievements. They will be released in time.