New 'mini-moon' around the size of a car orbiting the Earth

Bronwen Weatherby
Catalina Sky Survey

A new "mini-moon" has been discovered circling the Earth.

The asteroid, called 2020 CD3, is about the size of a car and is only the second of its kind to have circled the planet.

Astronomers who have been observing the space discovery confirmed the object has become gravitationally bound to Earth and now acts as a miniature moon.

However, it is predicted to be temporary having and estimated to have joined the Earth's orbit around three years ago.

It was detected on February 15 at the Catalina Sky Survey - a NASA-funded project at the University of Arizona's Lunar and Planetary Laboratory in Tuscon, Arizona.

Scientist Kasper Wierzchos tweeted the news writing: "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.”

Mr Wierzchos added: “It's a big deal as out of ~ 1 million known asteroids, this is just the second asteroid known to orbit Earth.”

The first was called 2006 RH120 and it stayed for around 18 months between September 2006 and June 2007 before it was eventually flung away again.

The new moon is between 1.9 and 3.5 metres across and is circling the planet about once every 47 days in an oval shape.

Not everyone is agreed on the mini-moon's trajectory however, Grigori Fedorets from Queen’s University Belfast said: “It is heading away from the Earth-moon system as we speak."

Tests still need to be carried out to confirm it is a temporary moon and not a piece of artificial space debris.

If found to be a mini-moon one astrophysicist at UH Manoa, Robert Jedicke, said it could be "extremely interesting"

And one day, a mini-moon could be brought back to Earth, "giving us a low-cost way to examine a sample of material that has not changed much since the beginning of our solar system over 4.6 billion years ago", he added.

The Moon is 2,000 miles wide and has been orbiting Earth for over four billion years.

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