Some astronomers assert that way back when the Earth had two moons – the one we know today and a much smaller one that perished after a few million years in orbit.

Some astronomers assert that way back when the Earth had two moons – the one we know today and a much smaller one that perished after a few million years in orbit.

It’s tough to pinpoint exactly when that was as the moons are estimated to have formed somewhere between 30 million years and a hundred and thirty million years after the solar system did. The solar system sprouted up some point around 4.6 billion years ago.

Regardless, a theory is that the mini moon - which likely measured about one-thirteenth the size of the other - was on a path similar to the larger one when it got pulled onto the big moon’s route.

The two subsequently collided, and the small moon was no more. Well, sort of no more.

The presence of a second moon also figures prominently in an explanation for why the two halves of our Moon are so very different.

It’s believed to be possible that the mysterious moon collided with the regular Moon at a speed of up to 67 hundred miles per hour. The impact then both flattened and fused it to the dark side of the larger satellite’s lunar surface.