Astronomers from the University of Arizona, United States, discovered a chunk of space rock they have dubbed a 'mini-moon', or, more formerly, 2020 CD3, orbiting the Earth, according to Live Science. The smallish asteroid was spotted by astronomers in Tucson, Arizona, on February 15.
The rare discovery was made by Kacper Wierzchos and Theodore Pruyne, research specialists for the Catalina Sky Survey, funded by NASA and the University of Arizona. The mini-moon is a space rock that has found itself bound in an Earth orbit. It is projected to circle the planet for anywhere from several months to a few years before it slips away or falls toward the surface, burning up in the atmosphere.
“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,” Wierzchos tweeted.
The astronomers suggested that the asteroid, with a diameter of between 1.9 and 3.5 meters, entered Earth's orbit some three years ago and may be gone by April. Such objects are known in astronomical circles as a “Temporarily Captured Object”.
“It’s a big deal as out of ~ 1 million known asteroids, this is just the second asteroid known to orbit Earth,” the researcher added.
The object was officially announced on Tuesday by the International Astronomical Union's Minor Planet Center, which collects observational data on asteroids, comets and other potential and actual natural satellites in the solar system.
The last cosmic interloper detected orbiting our planet was the 0.9 meter diameter 2006 RH120, which circled the earth for 18 months in 2006 and 2007.