With the help of China’s lunar mission Chang’e 1 and 2, scientists in China have published a new study that identifies multiple new craters on the surface of the moon. The study published in Nature journal on Tuesday has estimated that there are more than 1,00,000 craters on the moon.
The significance of this study is that with the help of these craters the history of the solar system can be understood in a better way. Scientists have described these impact craters as the lunar equivalent of fossils that are found on earth. The craters present the most dominant lunar surface features and record the history of the Solar System itself. With this study, the scientists have phenomenally increased the information that was earlier known.
Initially, there was a small number of recognized craters and dated craters, i.e., 7895 and 1411, respectively. However, with this study, the scientists have progressively identified new craters and estimated their ages with Chang’E data and stratigraphic information by transfer learning using deep neural networks.
Chinese scientists used data from their first and second lunar orbiters, Chang'e 1 and Chang'e 2. The two lunar orbiters identified nearly 1,09,956 new craters. Chang’e 1 and Chang’e 2 are unmanned spacecraft launched in 2007 and 2010, respectively.
Earlier this month Chang’e 5 landed on the moon to collect some moon rocks which it brought back for the scientists to study. However, this research was mainly conducted using artificial technology and sophisticated softwares.
Explaining the need to conduct this study, scientists explained that with the sixty years of advances in lunar exploration projects like the Luna missions and NASA’s Apollo programme, various lunar data, including digital images, digital elevation models (DEM) and lunar samples have accumulated.
With the help of visual inspection of images and DEM data by experts or automatic detection a large number of lunar craters, and consequently, many crater databases have been established. However, it has also generated a significant disagreement in crater number among existing databases due to the subjectivity of manual detection and the limitations of automatic detection with different types of data.
Since 1919, the International Astronomical Union (IAU) has recognized 9,137 lunar impact craters. Out of these the formation ages of 1675 lunar craters were aggregated by the Lunar and Planetary Institute (LPI) in 2015.
What also helped the scientists to get accurate results was the preserving nature of the Moon’s surface. Unlike earth, the Moon does not have water, atmosphere, or tectonic activity, factors that cause erosion. Hence the craters have remained intact and over 99 % of the lunar surface is more than 3 billion years old.