When no one was looking, a miniature "moon" in the night sky was already far away from
us. The miniature moon was a small satellite orbiting the Earth discovered by astronomers earlier this year, according to a study published
in the Astronomical Journal. And while it has now drifted away, it's likely that very
soon scientists will discover more Earth-like fans of your partner
.
In February, astronomers at the Catalina Sky Survey in the U.S. spotted
a dim object and named it 2020CD3.At the time
, astronomers couldn't be sure if it was a tiny satellite or a manmade object such as a rocket
booster. Over the next few months
Grigori Fedorets
of Queen's University Belfast in the United Kingdom
and her colleagues, using telescopes around the world, took more measurements of the dim
object and finally identified it as
a small satellite orbiting Earth.
The miniature "moon" is about 1.2 meters in diameter and entered
Earth's orbit about 2.7 years ago. Based on its color and brightness, it is likely to be made of silicate rocks
like many other objects in the belt of small planetesimals. In addition, the researchers tracked its orbit to try
to figure out where it came from before it entered Earth's orbit.