Images of the puzzling object have been released after some speculated it appeared to be a new “minimoon”.
Earlier this week, the scientific community was abuzz when astronomers found space rock “2020 CD3” has actually been circling Earth for three years.
Scientists say it is too soon to say for sure what the mystery object is and further research is required.
Some astronomers have suggested it could be an artificial object, while others say it might also be an old satellite, or space debris.
And others say the object is a rocky asteroid, which would mean it would be the only second natural satellite to be spotted around the Earth, other than the Moon.
‘NEW SPACE NEIGHBOUR’
Grigori Fedorets, the lead astronomer for the observations, said: “Either way this is a very compelling object and needs more data to determine what it is”.
Our new space neighbour was discovered on February 15 by astronomers at Arizona’s Catalina Sky Survey but will leave Earth’s orbit in the coming months.
John Blakeslee, head of science at the international Gemini Observatory, told The Independent: “Obtaining the images was a scramble for the Gemini team because the object is quickly becoming fainter as it moves away from Earth.
“It is expected to be ejected from Earth’s orbit altogether in April.”
Astronomer Kacper Wierzchos from the Catalina Sky Survey announced the discovery on Wednesday, saying: “BIG NEWS. 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.
“The object has just been announced by the MPC and its orbit shows that it entered Earth’s orbit some three years ago.
“The object has a diameter between 1.9 – 3.5 m assuming a C-type asteroid albedo.
“But it’s a big deal as out of ~ 1 million known asteroids, this is just the second asteroid known to orbit Earth.”
The mystery object is one of just a handful of Earthly “mini moons” ever discovered.
Images show the object glowing at the centre, with stars streaking from the movement of the telescope in tracking the object as it made its way around the Earth.
The news was announced the International Astronomical Union’s Minor Planet Center, which flags up smaller space objects.
“The object is temporarily bound to the Earth,” astronomers at the MPC said.
“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.”
We don’t know exactly how big it is yet – but astronomers estimate it’s roughly six to 12 feet.
That’s based on sunlight reflected from the object, allowing for a guess at its possible size.
The Moon is Earth’s only major natural satellite, but that doesn’t mean we’re all alone in our quiet corner of space.
A small natural object named 2006 RH120 was confirmed to have entered a temporary Earth orbit during 2006 and 2007.
And 2020 CD3 appears to be the second example of this kind of scenario.