Earth is getting a second moon—at least for a little while. This moon will come in the form of a small asteroid that will make precisely one orbit around the Earth before it begins its journey back through other parts of our solar system. This isn’t the first time we’ve seen something like this happen—Earth has always had a ‘fake moon’—but it is always a fun phenomenon to experience.
A new paper published in Research Notes of the AAS describes how these asteroids tend to become captured by Earth’s gravitational pull and even outlines the calculations that some researchers have made for the path of the asteroid that they believe will act as a bit of a new moon for our planet. Previous research has shown this happens quite often with asteroids—in 2006, an asteroid circled Earth for a year.
Another asteroid acted as a second moon for our planet for several years before leaving in 2020, as well. In this particular instance, though, researchers are looking at an asteroid that was discovered as part of the Asteroid Terrestrial-Impact Last Alert system in August. Research has previously shown this asteroid may be on a collision course with Earth. However, researchers suspect it will come just close enough to become trapped in Earth’s gravity.
From there, it will orbit our planet like a moon for around 53 days before being flung back out into the cosmos. The asteroid isn’t very large—only 10 meters across, based on calculations. Because it isn’t going to orbit the Earth very long, you’ll have a very limited time to see it. The researchers believe the asteroid likely came from somewhere in the Arjuna asteroid belt.
The asteroid belt is made up of several asteroids that orbit around the Sun, similar to Earth’s. Some have posited that the asteroid may actually be a piece of space junk. However, researchers say this is unlikely, as the would-be second moon has a path that fits an object with a natural origin, not a manmade object.