It seems the moon is harboring some alien debris, according to astronomers.
Strange minerals detected at the center of some of the moon’s deepest impact craters has long puzzled astronomers, but it now seems that the minerals may have Earthly origins. According to a newly published paper in the May 26 online issue of the journal Nature Geoscience, the minerals likely originated from asteroids striking the moon, and asteroid debris from impacts on Earth.
While the discovery itself is news, the data is far from groundbreaking. In fact, astronomers studying the moon have long known that minerals collecting at the center of lunar craters are the results of either debris ejected from Earth, or minerals unlocked by massive impacts on the lunar surface. However, the latter was not confirmed until recently, when astronomers, studying simulated models of lunar impacts, observed similar collection points to those observed on the moon.
Scientists found that impacts occurring at speeds below miles per hour (43,000 kph) do not vaporize on impact. Instead, it often shatters into a shower of debris, some of which ends up piled at the center of the crater. In other cases, Earthly material discovered on the moon likely came from pockets deep in the Earth, leading geologists to suspect massive impacts carved out unusual minerals that later landed on the peaks of many lunar impact craters on the surface of Earth’s nearest neighbor.
The discovery explains why some minerals found on the lunar surface do not appear throughout the moon’s subsurface. Geologists say the discovery could provide a nearly perfectly preserved specimen of the early Earth, including some of Earth’s protobiological materials, which are no longer available. Scientists first began to suspect that the some of the minerals discovered on the lunar surface had an alien origin. spinel and olivine, two of the most prominent minerals discovered in the center of craters on the moon, are not found in the lunar soil. They are, however, components of asteroids and meteorites, according to astronomers.
The study comes as scientists have focused attention on the moon in an attempt to better understand how it evolved over the past several billion years. A recently observed impact on the moon produced the brightest flash ever observed, according to NASA. The explosion on March 17 was the biggest seen since the space agency began observing the moon, watching for meteoroid impacts. To date, according to NASA scientists, more than 300 strikes have been recorded.
According to another unrelated study published earlier this month, the moon seems to have its fair share of meteoroid impacts. According to astronomers, the moon, which does not have an atmosphere, may be bombarded upwards of once a day, and the impacts may be far more violent than previously thought.
NASA has already sent a pair of probes to the cosmic body. GRAIL I and GRAIL II, a pair of probes launched by the U.S. space agency. spent just over a year mapping the lunar surface and collecting data on the moon’s gravitational field. The probes were then programmed to crash into two separate lunar mountains, providing scientists with additional data.
The renewed focus is largely part of a larger effort to increase missions to the moon. A number of private companies have already announced plans to begin building lunar colonies, which is increasing pressure on space agencies around the world to collect more data on the lunar environment.
The paper is co-authored by Jay Melosh from Purdue University in Indiana and Erik Asphaug of the School of Earth and Space Exploration at Arizona State University.
You can see a full list of all of the impacts recorded on the moon here.