New theory about the formation of the moon has scientists intrigued.
The moon is one of the most studied and most predictable objects in the sky, but questions still linger about how it was originally formed.
According to an article in the Washington Post, many astronomers believed the moon was formed when the Earth and another planet may have collided in the infancy of the universe, breaking off a chunk of Earth that became the moon as we now know it.
But some have come to question that scenario, as new information comes to light, leaving others to look for another explanation. One of the problems with the “giant impact” theory is that the chemical composition of the moon is almost identical to the Earth’s, and if another planet had indeed stricken the Earth, it seems to reason that some of its chemical makeup would have been left behind.
Along comes a team of Israeli researchers who are offering a different explanation. They say the moon could have been formed, not as a single chunk knocked off by a giant planet, but a bundle of smaller pieces sent flying into space by a series of smaller impacts over time.
Lead author Raluca Rufu, a planetary scientist at the Weizmann Institute of Science in Israel, says we know the time around the formation of the solar system was a chaotic time, with all manner of objects bumping into planets and each other, and that type of collision with the planet Earth would probably have happened quite frequently.
And each collision would have sent chunks of rock flying off of the Earth into orbit around the planet. As they cooled, they would migrate away from the planet and into contact with other similar rocks and form a series of moonlets.
The researchers say about 20 of these moonlets could have combined to form the moon we see in our night skies today, and could also explain why the moon’s chemical makeup is so similar to that of the Earth.
The team was able to produce models that show the smaller impacts could indeed cause sizable moonlets, but the next challenge is to figure out how the smaller moonlets came together to form the larger moon.
Now that the research has been published in the journal Nature Geoscience, the team is setting out to prove the second part of the hypothesis.