Visualizations by
Ernie Wright
Released on October 16, 2019
2I/Borisov is an interstellar comet, meaning that it came from outside our solar system. It is the first such comet ever observed, and only the second interstellar object of any kind, after the asteroid-like 'Oumuamua. The comet was discovered by amateur astronomer Gennadiy Borisov on August 30, 2019, using a 25.6-inch (0.65-meter) telescope that he designed and built specifically to hunt for small, faint objects.
The path of the comet enters our solar system from the north and crosses the ecliptic, the plane of the Earth's orbit around the Sun, on October 26, 2019. The best chance to see it is during December when it makes its closest approach to the Sun (December 8) and the Earth (December 28). The comet will then be passing through the constellations Crater and Hydra. At mid-northern latitudes, these are fairly low and to the south about two hours before sunrise. The comet will be much too dim to see without a telescope, and it'll be a challenge even in fairly large amateur instruments. Its maximum brightness is currently predicted to be only magnitude 15, about as faint as Pluto.