Scientists found that asteroid impacts on the Moon millions of years ago correlated exactly with some of the largest meteorite impacts on Earth, such as the dinosaur-killing event.
Recently, mankind achieved the monumental task of navigating a spacecraft to an asteroid millions of kilometers away and impacting the space rock in order to change its trajectory. This mission, called DART, was a test mission to see where this could ever be done and to prepare should a space rock ever threaten our planet with collision. However, understanding impact craters on Earth and the Moon can also help us prepare.
Meteorite impacts on Earth, such as the one that wiped out the dinosaurs, coincided exactly with asteroid impacts on the moon millions of years ago. This study, conducted by Curtin University, also found that significant impact events on Earth weren’t stand-alone events but rather involved a series of smaller ones. The study provides new insight into asteroid dynamics in our inner solar system, including the possibility of asteroid impacts on Earth.
Researchers studied microscopic glass beads from lunar soil brought back to Earth as part of China’s Chang’e-5 lunar mission, which was launched in December 2020. A timeline of meteorite bombardments can be revealed by the age distribution of the glass beads, which were created by heat and pressure from meteorite impacts.
The findings suggest the timing and frequency of asteroid impacts on the Moon may have mirrored those on Earth, providing us with more insight into the evolution of our own planet, according to lead author Professor Alexander Nemchin, from Curtin University’s Space Science and Technology Centre (SSTC). In order to determine how and when these microscopic glass beads from the Moon formed, Professor Nemchin combined a wide range of microscopic analytical techniques, numerical modeling, and geological surveys.
Scientists found that some of the age groups of the lunar glass beads coincide precisely with the ages of some of the largest terrestrial impact crater events, including the Chicxulub impact crater responsible for the dinosaur extinction event.
According to the study, there were likely to be a number of small impacts associated with large impacts like Chicxulub 66 million years ago. If this is correct, impacts on the Moon may provide valuable information about Earth’s impacts or impacts on the inner solar system.
The Chicxulub crater was formed when a massive asteroid, approximately 10 kilometers (6.2 miles) in diameter, impacted the Earth. The impact was so powerful that it produced a gigantic crater estimated to be 180 kilometers (110 miles) in diameter and over 20 kilometers (12 miles) in depth. In addition to being the second largest impact structure on Earth, its peak ring is the only one that can be directly studied by scientists.
According to Associate Professor Katarina Miljkovic, another co-author from Curtin’s School of Science and Technology, future comparative studies could provide more insight into Moon’s geological history. To uncover other significant Moon-wide impact events and to gain new insight into how impacts may have impacted life on Earth, Associate Professor Miljkovic said it would be important to compare these Chang’e-5 samples with other lunar soils and crater ages.