Scientists discovered a small asteroid that seems to follow the Earth, just like a satellite. Its name is 2016 HO3, and it was first observed by the Pan-STARRS 1 telescope from Hawaii.
NASA says that the quasi-satellite has been a companion to Earth for almost a hundred of years, and it will still keep close in the next centuries.
The small asteroid is not in fact following the Earth, but it has an orbit so similar to that of our planet that it seems like the two cosmic objects are traveling together through space.
Scientists have calculated that the size of the asteroid is between 120 and 300 feet long.
The distance between the 2016 HO3 asteroid and Earth is at least 38 times bigger than the one to the moon. There is no danger of collision. Researchers say that the object is too distant to be a real satellite to Earth.
„Since 2016 HO3 loops around our planet, but never ventures very far away as we both go around the sun, we refer to it as a quasi-satellite of Earth,” said Paul Chodas, from the Center for Near-Earth Object Studies in Pasadena.
The next time when the asteroid will come close to Earth will be on the 9th of November 2030, when the distance to Earth will be of 9 million miles.
The asteroid’s orbit is a bit tilted, which makes it go up and down in comparison to Earth.
When orbiting the sun, the quasi-satellite stays half of the time closer to the sun and half of the time closer to Earth. As its orbit is longer than the one of our planet, the small rock either falls behind or gets to be ahead in following the path around the sun.
The quasi-satellite orbit has a twist as it can easily drift away from the Earth. However, our planet’s gravitational force is strong enough to keep the asteroid close, so it never goes away more than 100 times the distance to the moon.
Researchers describe these movements and shifts in orbit as a dance with the Earth.
In 2003, the scientists observed a similar Earth companion that had a similar orbit to the sun. At the present moment, this decade old asteroid is no longer with our planet.
NASA’s Center for Near-Earth Object Studies has published a list with all known asteroids, their orbit details, and the dates for all close approaches.
Image Source: Wikipedia