October's full moon will have some company this month now that a mini-moon is in Earth's orbit. Here's what you should know about the second moon.

The Earth has got itself a new moon. The new satellite is temporary: it will leave again at the end of November. And it is very small, at just 10 metres across.

Scientists call such phenomena mini-moons. The asteroid was found by a group called ATLAS, which stands for Asteroid Terrestrial-impact Last Alert System, in August. The researchers who found it published a nonpeer-reviewed study about the asteroid.