Among the star-studded comets on his way to visit us, he was officially named after the amateur astronomer he discovered.
2I / Borisov was formerly known as C / 2019 Q4 Borisov. "I" stands for "Interstellar" and "2" because this is only the second seen so far behind 2017's 1I / & # 39; Oumuamua.
His recognition as an interstellar subject is not a surprise, given that it was apparently his distant origin within days of seeing Ukrainian heavenly leader Gennady Borisov in August on his home telescope.
"After a week of observations by amateur and professional astronomers around the world, the Small Planet Center was able to compute a preliminary orbit, which suggested that the object was interstellar," the International Astronomical Union said.
"The orbit is now well known enough, and the object is unambiguously interstellar in origin; received its final designation as the second interstellar object, 2I. In this case, the IAU decided to follow the tradition of naming commercial objects after their discoverers, so the case was named 2I / Borisov. "
Its orbit is hyperbolic, which means it has enough velocity to avoid the gravitational pull of the sun. Its origin is unknown, but the newspaper of Polish astronomers suggests that it may have been followed by binary star Kruger 60, 13 years away from light.
"When you search for a home system of interstellar bodies, you should look for close proximity at a very low relative speed to the order of only a few kilometers per second," they wrote.
"We have found that the Double Kruger 60 is a good candidate for this comet's home system."
Unlike Omuamuu, seen only at the exit, Borisov has yet to arrive. It made its closest approach to the sun on December 7, about twice the Earth's distance to the sun.
It will be easiest to observe from Earth in December and January, but only from the southern hemisphere, according to space.com. It is not known if it will be visible to the naked eye, but it is already beginning to form a tail.
Its size is estimated at several kilometers through, and its speed is 150,000 km / h.