Yes, Earth is getting a temporary second moon

Viral social media posts claim Earth is getting another moon for a short period of time. 

“Earth is set to temporarily obtain another moon on September 29th. The asteroid known as a ‘mini-moon’ is expected to make a single orbit journey around Earth, ending on November 25th,” a post with 19 million views says.

Google Trends shows a spike in people searching whether there’s a second moon and if it can be seen from Earth. 

Is Earth getting a second moon?

Yes, Earth is getting a second moon for a short period of time.

Earth is getting a second moon, specifically a “mini-moon.” In August, an asteroid, known as 2024 PT5, was spotted on the University of Hawaii and NASA’s Asteroid Terrestrial-impact Last Alert System. 

“Earth can regularly capture asteroids from the Near-Earth object (NEO) population and pull them into orbit,” a 2024 report published in Research Notes of the American Astronomical Society (AAS). This typically occurs when the asteroid or object’s geocentric energy turns negative if it flies closely towards Earth.

NASA defines “naturally-formed bodies that orbit planets” moons or planetary satellites.  

It’s not the first time Earth has gotten a “mini-moon.” The phenomenon most recently happened in 2022 and in 2020. 

Is the second moon permanent?

No. The second moon is temporary. 

Earth’s second moon will only be around for two months. This miniature moon is projected to be in Earth’s orbit between Sept. 29 and Nov. 25, the AAS report says.

When an object is pulled into Earth’s orbit, it’s typically considered either a “temporarily captured flyby” or a “temporarily captured orbiter,” the report explains. 

A temporarily captured flyby happens when the object doesn’t complete a revolution around Earth, while a temporarily captured orbiter completes one or more revolutions.

As the upcoming “mini-moon” is predicted to follow a “horseshoe path,” it will be in line with what is considered a temporarily captured flyby.

Will the second moon be visible from Earth?

No, the second moon will not be visible from Earth.

The “mini-moon” will not be able to be seen from Earth due to its small size and position while in orbit. 

The “mini-moon” is approximately only 10 meters wide and will follow a “horseshoe path” instead of completing a full revolution, so it will be very difficult to see the asteroid from Earth. 

If you want to see the mini-moon, you will need a professional telescope.

“The object is too small and dim for typical amateur telescopes and binoculars. However, the object is well within the brightness range of typical telescopes used by professional astronomers,” Universidad Complutense de Madrid professor and author of the 2024 report Carlos de la Fuente Marcos told Space.com.