Many of the planets in our solar system have multiple moons, and some even have dozens of large objects cruising around in orbit around them. Earth, by contrast, has just one large moon. Thanks to its solo nature, we even just call it “The Moon,” which is convenient, but that doesn’t mean that other natural objects couldn’t also get snagged by our planet’s gravity, and researchers think they might have just spotted a “mini moon” orbiting our planet.
The pint-sized object known as 2020 CD3 was acknowledged by the Minor Planet Center after being spotted during the NASA-led Catalina Sky Survey. At this point, it’s unclear exactly how long the rock will hang around, but for now, it’s Earth’s newest buddy.
When I say “pint-sized” I truly mean it. The asteroid is tiny, and even the upper estimates suggest the rock is no larger than around 3.5 meters in diameter. That’s a very small object, but it’s still large enough to be spotted from ground-based sensors and, if it hangs out long enough, it could qualify as a “mini moon.”
Earth isn’t a particularly huge planet, but its gravitational pull is still strong enough to snag some objects as they pass by. Oftentimes, these objects simply slingshot their way around our planet and speed back out into space, but occasionally they approach at just the right angle to enter an orbit.
These objects rarely pose a threat to Earth, and even if an object the size of 2020 CD3 were to tumble toward Earth rather than flying back out into space, friction with Earth’s atmosphere would likely tear it apart and incinerate most if not all of its material. For now, we’ll just have to enjoy our new neighbor for however long it decides to stick around.