The truth behind Earth’s newly discovered ‘second moon’ and why it won’t be here for long
Turns out Earth has a little companion that's gone undetected for decades - but is it a second moon?
Back in August, scientists from the Pan-STARRS observatory in Hawaii discovered a new celestial object called 2025 PN7.
Archival data revealed that the object has been in an Earth-like orbit for around six decades.
Some four million kilometers (2.5 million miles) away from our planet, it's approximately 10 times farther away than the Moon.
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This means it has no impact on Earth's tides, gravity or daily life.
Measuring up at just 52 feet long, the size of a city bus, the space object has been labeled a quasi-moon.
Many headlines have celebrated us now having two moons, while some have claimed NASA has confirmed this news.
That's not true; here's what really going on...
What is a quasi-moon?
The Planetary Society explains that quasi-moons are actually asteroids, but earned their title because, 'from a certain vantage point, they appear to act more like moons'.
From our planet's point of view, quasi-moons appear to be orbiting the Earth, but, like us, they're actually orbiting the Sun.
So quasi-moons are a bit of an optical illusion, really.
2025 PN7 takes a year to orbit the Sun - the same as Earth - and turns out, the asteroid has been with us since the 1960s.
So why has it taken us so long to detect it?
Carlos de la Fuente Marcos, a researcher at the Complutense University of Madrid, who wrote a paper on 2025 PN7, explained why, as per CNN.
"It can only be detected by currently available telescopes when it gets close to our planet as it did this summer," he said.
"Its visibility windows are few and far between. It is a challenging object."
De la Fuente Marcos reckons 2025 PN7 comes from the Arjuna asteroid belt; a group of small asteroids between Mars and Jupiter.
Why won't 2025 PN7 last forever?
Despite keeping Earth company - from a distance! - for so long, 2025 PN7 won't stick around forever.
Scientists reckon the quasi-moon will stay stay nearby for another 58 years, until 2083.
By then, the gravitational pull of the Sun will have moved it on to a new path.
It's not our only temporary quasi-moon, either.
Last August, asteroid 2024 PT5 was spotted by the NASA-funded ATLAS telescope in South Africa.
Scientists reckoned the 10-meter wide space rock was actually a chunk of our moon. How's that for some lunar-ception?
The asteroid only stuck around for a few months, until November 2024.
Who knows how many other quasi-moons we might find?
Ellie Kemp