Asteroid 2020 CD3 was discovered by American astronomers Theodor Pruyne and Kacper Wierzchoś at the end of February. Scientists reported that the gravitational field of the Earth captured a celestial body three years ago, but this phenomenon attracted the attention of scientists only now. An asteroid is a carbon body with a diameter of 1.9 to 3.5 meters.
Most asteroids pass by our planet or burn in its atmosphere. In 2012, the supercomputer calculated that out of 10 million virtual asteroids, only 18 thousand fall into low Earth orbit. Scientists say that the number of such objects in the orbit of our planet can be measured in thousands, but they are extremely difficult to detect due to their small size.
“The presence of small Earth satellites was assumed earlier; there is nothing unnatural in them,” comments the Russian astronomer, director of the Irkutsk State University Astronomic Observatory, a member of the Russian Geographical Society, Sergey Yazev. “Before, we had not encountered them, since they do not threaten everyday space life – all of the artificial satellites are located much closer to Earth than their orbits. But, of course, it is necessary to search for, discover and study them, since space activity is booming.”
Asteroid 2020 CD3 became the second currently known temporary satellite of the Earth. The first such object was the asteroid 2006 RH120, which "accompanied" our planet for 18 months - from 2006 to 2007.
American astronomers are sure that such mini-moons are promising for research: it is less expensive to send a spacecraft to them than to asteroids, and they can occur in close proximity to Earth. Temporary mini-moons are just like asteroids, only much more accessible.
Russian astronomers are less optimistic. "The simplicity of studying the temporary satellites of our planet is very doubtful. Yes, they are closer, but their speed, eccentricity, and orbital inclination can be such that, with the available engines, the maneuvers of the spacecraft can be more difficult than during the slow but sure chase after a comet or an asteroid," Sergey Yazev considers.
According to astronomers, 2020 CD3 will leave the orbit of the Earth by April.