Comet 2I/Borisov, the first-ever interstellar space comet, will sweep around the Sun this weekend. On Dec. 28 it’ll have its closest approach to the Earth.
Borisov is remarkable because all other known comets have come from within our own solar system. Borisov, in contrast, has travelled 100 million miles or so from some other solar system (scientists don’t know which one) to visit us. This Sunday it’ll slingshot around the Sun before beginning its return journey to . . . wherever.
Comet Borisov, of course, reminds us of another famous Christmas comet–Comet Kohoutek, which caused such a stir when it swept around the Sun in December of 1973. Astronomers then wondered if Kohoutek might be an interstellar comet, too. (It wasn’t.) An excellent and entertaining fictional account of Comet Kohoutek, I’m told, can be found in the novel THE NIGHT OF THE COMET, by Mr. George Bishop, Jr.
It’ll be too faint to see with the naked eye, but you can read more about it here at CNN.com, and track its path here at https://svs.gsfc.nasa.gov/4758
