"NASA Confirms Earth Has Gained A Temporary 2ND Moon That Will Remain in Orbit Beside Us Until 2083,” reads a claim made by the Facebook account What the Fact, an account that says it is dedicated to "the latest space science & astronomy news”. Its second moon claim was featured in a post that garnered more than 16,000 reactions. The claim was also widely circulated on X, with some posts garnering more than 3 million views.
To illustrate this claim, the posts feature an image generated by artificial intelligence showing the Earth with two moons of roughly the same size, suggesting the existence of a new heavenly body similar to the Moon currently in orbit around our planet.
This is a screenshot of the post that What the Fact shared on Facebook on December 30, 2025. © Facebook
The confusion seems to hail from the discovery made last July by researchers at the Complutense University in Madrid of a small asteroid baptised "2025 PN7". This asteroid was first spotted through the Pan-STARRS1 telescope at the Observatory in Haleakala, Hawaii. While it has an Earth-like orbit, that does not make it a “temporary second moon”.
Why are people talking about a 'second moon'?
Our team spoke to Éric Lagadec, an astrophysicist at the Côte d’Azur Observatory:
"'2025 PN7' isn’t a new moon. A moon orbits around a planet that it is linked to by gravity, like our moon that orbits Earth. This asteroid, however, is not orbiting our planet. It is what is called a "quasi-moon" or a "quasi-satellite": it orbits the sun, but its trajectory follows Earth’s trajectory, which gives the impression that it is following it."
According to NASA, "moons orbit planets and dwarf planets. They also orbit asteroids". 2025 PN7, on the other hand, doesn’t orbit the Earth; it orbits the sun (see the image below or check out NASA’s Small-Body Database Lookup (SBDB), which has information about so-called small bodies within our solar system).
The blue line shows the Earth’s orbit around the sun. The grey line shows 2025 PN7’s orbit around the sun. © Small-Body Database Lookup
The asteroid, which has a diameter of around 19 metres, isn’t gravitationally linked to the Earth – unlike the moon. It doesn’t have any impact on our planet – for example, it has no bearing on the tides, unlike our moon. It also isn’t visible to the naked eye from Earth.
Lagadec says that the confusion stems largely from images shared by some social media users, which depict the asteroid as a similar size to our moon. In reality, our moon has a diameter of around 3,400 kilometres, while 2025 PN7’s diameter is only 19 metres.
"This type of image can feed into conspiracy theories about the moon,” Lagadec said.
This article has been translated from the original in French by Brenna Daldorph.
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