A small car-size body measuring just 1.9 to 3.5 metres (6.2 to 11.5 feet) across has been found in an unstable Earth orbit, taking 47 days to complete one trip around the planet on a path that carries it well beyond the moon. Discovered by astronomers with the Catalina Sky Survey in Arizona on 15 February, the presumed asteroid, known as 2020 CD3, likely was captured by Earth’s gravity three years ago.
“BIG NEWS,” tweeted co-discoverer Kacper Wierzchos:
BIG NEWS (thread 1/3). Earth has a new temporarily captured object/Possible mini-moon called 2020 CD3. On the night of Feb. 15, my Catalina Sky Survey teammate Teddy Pruyne and I found a 20th magnitude object. Here are the discovery images. pic.twitter.com/zLkXyGAkZl
— Kacper Wierzchos (@WierzchosKacper) February 26, 2020
The Minor Planet Center in Cambridge, Massachusetts, confirmed the discovery, saying trajectory analysis indicates 2020 CD3 is “temporarily bound to the Earth. No evidence of perturbations due to solar radiation pressure is seen, and no link to a known artificial object has been found. Further observations and dynamical studies are strongly encouraged.”
The 8-metre Gemini North telescope in Hawaii did just that, capturing an image of the body on 24 February. It is rapidly dimming as it moves away from Earth and John Blakeslee, head of science at the international Gemini Observatory, said “it is expected to be ejected from Earth’s orbit altogether in April.”
Despite its small size and descriptions saying the body is “car size,” Elon Musk, who famously launched a Tesla Roadster sports car into deep space in 2018, tweeted in a response to New Scientist magazine: “it’s not mine.”