According to scientists, the Earth may have once had a small second moon.
Researchers argue that the smaller moon disappeared in a collision with its “big sister.” They believe that this would explain the mysterious existence of mountains on the far side of the Moon.
Researchers have tried to understand why the visible side of the Moon is flat and cratered, while the rarely-seen hemisphere is heavily cratered and has mountains with altitudes as high as 3,000 m. In time, numerous theories have been proposed to explain these aspects.
Recently, researchers have argued that the Earth was hit by a planet the size of Mars about four billion years ago. Debris resulting from the impact were aggregated and led to the formation of the Moon.
However, scientists believe that it could have been another smaller celestial body, composed of the same material, that remained locked in a gravitational field located between the Earth and Moon.
Dr Martin Jutzi from the University of Bern, Switzerland said that after millions of years of captivity between the two planets, the moon came into a little collision with its “big sister”, at a speed of less than three kilometers per second.
Scientists claim that the impact would have led to the accumulation of material on the lunar crust and would also have redistributed the magma on the visible side of the Moon.
Researchers involved in this study hope that data from NASA missions will support or refute their theory.
Details of these theories have been published in the journal Nature.