The far side of the moon
The image above was taken by the Soviet Union’s Zond 8 spacecraft to observe and study the side of the moon that cannot be seen from Earth.
The terrain is very different than the near side and recently UC Santa Cruz researchers published a study as to why that is. They theorize that there was a “giant splat" from an ancient smaller moon that caused this feature:
"The mountainous region on the far side of the moon, known as the lunar farside highlands, may be the solid remains of a collision with a smaller companion moon. The near side is relatively low and flat, while the topography of the far side is high and mountainous, with a much thicker crust. A Mars-sized object collided with Earth early in the history of the solar system and ejected debris that coalesced to form the moon. The study suggests that this giant impact also created another, smaller body, initially sharing an orbit with the moon, that eventually fell back onto the moon and coated one side with an extra layer of solid crust tens of kilometers thick."
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