Does the earth have two moons? What is 2025 PN7? What has Nasa said?
A new object has arrived in the Earth’s part of solar system - leading to excitable claims that we now have two moons.
Amid the jokes about the Star Wars Death Star (”That’s no moon”) and conspiracy theory witticisms over whether America would have to fake another moon landing, there is some truth in this.
Here’s what’s come to light in our skies...
Does the Earth have two moons?
No (but slightly yes). There is a new object in space near Earth, which will stick around until 2083.
Its official name is 2025 PN7 and it is also called Buwan. It’s a small, near-Earth asteroid that can be categorised as a quasi-satellite.
It was discovered observed on August 2 this year by the Pan-STARRS 1 telescope at Haleakala Observatory in Hawaii, and is a member of the member of the Arjuna asteroid group, which is near Earth and has an orbit like Earth’s.
What is 2025 PN7?
When scientists looked back through the records they realised that 2025 PN7 had been unknowingly picked up as long ago as 2014. It’s thought it has been following Earth’s orbit for at least 60 years and is likely to remain here for about 128 years - so until about 2093 at the very latest.
It’s not a moon - it’s an asteroid that is between 18m and 36m wide and is moving in sync with us. It’s far too small to show up to the naked eye by reflecting any sunlight like the Moon does, and it’s not really orbiting us - it’s just that it’s path is coinciding with ours for the moment.
Could 2025 PN7 be dangerous?
No. It’s not going to hit us, and its size and distance from Earth - about 4,000,000km, 10 times further away than the moon - means it cannot alter tides or gravity - or indeed any of the other things that the Moon is said to influence, such as the behaviour of children.
What has Nasa said?
Despite widespread reports on social media that Nasa “has confirmed that the Earth has two moons”, it does not appear that Nasa has said anything of the sort. Not only is it astronomically (in the original meaning of the word) illiterate to claim 2025 PN7 is a moon, Nasa has been closed since the beginning of this month because of the US government shutdown. Nasa hasn’t said anything about anything since September.