Earth to Get Another Moon This Month

But Don't Get Too Attached

Skywatchers, get ready for a rare celestial event! This month, Earth will temporarily gain a second moon, albeit a small and temporary one. But don't get too attached, as this celestial visitor will only be around for a short while.

A Captured Asteroid

The incoming "moon" is actually an asteroid, designated as 2023 BU. It's a small space rock, measuring just 3.5 to 8.5 meters in diameter, making it about the size of a small car or large SUV.

2023 BU was discovered by astronomers in Crimea on January 21, 2023, and is believed to have been captured by Earth's gravity during a close approach about a year ago.

Temporary Companion

The asteroid will make its closest approach to Earth on January 26, 2023, passing about 3,600 miles (5,800 kilometers) above the surface. This is well within the range of our geostationary satellites, but still far enough away to pose no threat to our planet.

After its closest approach, 2023 BU will remain in an elliptical orbit around Earth for about three months before being ejected back into space.

No Visible Effects

Due to its small size and distance from Earth, 2023 BU will not be visible to the naked eye. Even with telescopes, it will be challenging to spot this tiny moon.

However, astronomers will be closely monitoring the asteroid's trajectory to study its behavior and learn more about how small celestial bodies interact with planets.

A Unique Occurrence

While Earth has had temporary moons in the past, such as the quasi-moon Kamo'oalewa, the capture of an asteroid as a moon is a relatively rare event.

Scientists estimate that 2023 BU is the first asteroid to become a temporary moon of Earth since 2006 RH120, which orbited our planet for about a year before escaping.