The mysterious "jelly-like" substance discovered by the Chinese lunar rover "Yuytu-2" in a small impact crater turned out to be rock that melted from the fall of the meteorite, and then formed a dark green shiny glassy mass.
For the first time, this brilliant substance was found by the lunar rover at the end of July 2019 and came to the attention of Chinese researchers during the decoding of the observation diary "Yuytu-2". The substance has been described as "jelly-like", which is an unusual description of a find from a dry and dusty moon.
Later images showed that the substance is indeed something glossy, but probably not "jelly-like" at all. A detailed analysis based on data from visible and near infrared spectrometers confirmed this hypothesis.
In particular, the images allowed scientists from the Chinese Academy of Sciences to analyze the light reflected from the substance and determine its chemical composition.
“According to our analysis, the regolith is composed mainly of plagioclase (about 45%), pyroxene (7%) and olivine (6%) - pretty standard for lunar rock. Due to poor lighting, the composition of the vitreous substance was a little more difficult to recognize, and we were able to consider only plagioclase in an amount of about 38%,”the researchers write.
CNSA / CLEP
The researchers also determined that the dark greenish material was approximately 52 x 16 centimeters in size. It is very similar to the two Apollo 15 and 17 samples: lunar sample 15466 and lunar sample 70019, respectively. Both of these samples, obtained from impact craters, are classified as breccias, a type of rock made up of debris held together by thinner material.
The researchers concluded that the material was formed during the impact of a meteorite. As a result of the high temperature action, part of the regolith melted and mixed with the unmelted regolith, forming a breccia.
Scientists note that this material was probably formed elsewhere. The Von Karman crater is only 2 meters in diameter. The estimated diameter of an impactor that could create a crater is only 2 centimeters in size - too small to create an impact melt of 52 × 16 centimeters.
“Consequently, the impact molten breccia was unlikely to have formed in the crater where it was found and was most likely found elsewhere, after which it was ejected into a 2-meter fresh crater,” the researchers conclude.
