A tiny mini-moon has orbited Earth since April
· BehindLines newsroom
Since April, Earth has had a small companion: an asteroid named 2026 QQ8, temporarily held by its gravity. According to Live Science and Sky at Night Magazine, astronomers have confirmed it as a "mini-moon". The two outlets announce its departure, but not on the same timescale: January 2027 for Live Science, December or perhaps January for Sky at Night.
A discovery in stages
According to Sky at Night, the Hungarian astronomer Krisztián Sárneczky spotted the object on 20 August 2026; Live Science places that observation in August. His report to the Minor Planet Center, which logs new objects in the solar system, first led people to think it was space debris. Follow-up observations with the 2.2-metre telescope of the University of Hawaii and with the Lowell Discovery Telescope, in Arizona, then confirmed a natural origin. According to Live Science, the Minor Planet Center officially registered the object on 29 October; Sky at Night dates its designation as a moon to that day.
A tiny visitor
The size estimates do not match. Live Science, citing the International Astronomical Union, gives about 2 metres; Sky at Night puts it at 1 to 2 metres. According to Live Science, 2026 QQ8 takes 359 days to go around the Sun. Both outlets say it passes close to Earth roughly every ten years. Sky at Night explains that it normally stays outside the "Hill sphere", the zone where Earth's gravity outweighs the Sun's, and that it is believed to have crossed it in April 2026, which placed it in orbit around Earth. It is currently about one and a half times the distance of the moon, according to both outlets, and it cannot be seen with an amateur telescope, Sky at Night notes.
Nothing to worry about
Both sources stress that the object is too small to threaten Earth: if it headed our way, it would burn up on entering the atmosphere. Sky at Night adds that professional astronomers are watching it closely, not out of fear, but to understand how such temporary satellites are captured.
Not a first
According to Live Science, the first known mini-moon, 1991 VG, was about 10 metres across when detected in November 1991. Astronomers now estimate that Earth often has at least one, most staying less than a year and a few able to linger for decades. Sky at Night cites other past mini-moons: 2020 SO, 2020 CD3 and 2024 PTS. The magazine also reports that some astronomers think there could be up to half a dozen at once, better spotted thanks to technical progress. Live Science expects new telescopes, including the Vera C. Rubin Observatory (Chile), to detect more of them.
Why it matters
These small visitors pose no danger, but studying them helps explain how Earth captures such temporary satellites, according to Sky at Night. The departure dates remain estimates, and the two outlets do not agree on the timetable.