From September 29 until November 25, 2024, Earth’s moon is going to have its own fun-sized replica. This little guy, with a diameter of only 33 feet, is expected to orbit around the Earth for the next two months before departing and continuing its journey through space.
“Mini-moons” are near Earth objects (NEOs) that are captured by Earth’s gravitational pull, and, as a result, become stuck in our orbit for a period of time. These can be a variety of objects in space: asteroids, comets, or even chunks of rock blasted off from other planets or moons when two celestial bodies collide. Eventually, NEOs manage to break free of Earth’s gravity and will be launched back into space to orbit the sun, but it’s possible for them to come back and orbit Earth again.
Mini-moons are not uncommon or unheard of — astronomers detected one in 2020 and multiple throughout the 90s. Calling the moon’s new friend a “mini-moon” is also a bit of an exaggeration, because it is not visible with the naked eye, or even with an amateur telescope. To see this chunk of space rock, you’re going to need a powerful, research-grade telescope used by professional astronomers, meaning the average person won’t be getting a glimpse of it anytime soon.
Moreover, even if you can somehow catch a glimpse of 2024 PT5 (the name given to this mini-moon), it may pale in comparison to seeing Earth’s regular moon. The moon has a diameter of 2,159 miles, which is roughly 350 thousand times larger than the diameter of 2024 PT5. Compared to Earth’s moon, PT5 will look like a speck of dust, or a single pixel, next to the moon.
The bright side of 2024 PT5’s tiny size is that it won’t affect our tides in the slightest or pose a threat to our planet in general. If we had another moon the size of our moon (that is, another body of rock visible in the sky), there would likely be some very catastrophic events, such as our tides being eight times higher than they are now. This would create pronounced erosion issues, more solar eclipses, shorter lunar cycles, and a myriad of other problems that would make building permanent civilizations on Earth much harder.
So, despite our inability to easily see 2024 PT5 while it’s orbiting us, knowing it’s there is enough to satisfy curiosity. PT5 is also expected to pass by in 2055, along with various other mini-moons that have orbited us before being expected to come back and say hello in a few decades.
