Here's something interesting to ponder about. Most of us have heard about the theory that the moon was created after a Mars-sized object struck the Earth, launching a chunk of material from the Earth into space.

It's a plausible theory, but one that begs the question: if true, then how can we be sure that only one chunk of debris was thrown out into space?

With this in mind, scientists are now thinking that at some point in the far past, Earth actually had several moons as a result of the impact, including the ones that we have right now. These objects, which were trapped in Earth-Moon Lagrangian points, are referred to as Trojans.

According to Jack Lissauer of the NASA Ames Research Center, the Trojan satellites probably stuck around in the Earth-Moon Lagrangian points and eventually drifted away. The gravitational pull from the Earth and the Moon probably tugged the other moons away from the points, sending some of them crashing or drifting off into space.

"They would have resembled very bright stars," Matija Cuk, astrophysicist from the University of British Colombia said, referring to the moons that are estimated to span tens of kilometres across.