Image Credit: Gemini Observatory / NSF / AURA
A two-color composite image of the visiting comet.
Astronomers have revealed that comet 2I/Borisov is remarkably similar to comets from our own solar system.
First observed on August 30th, the comet, which is the second confirmed interstellar visitor to our solar system, was announced last month by the Minor Planet Center (MPC) at Harvard University.
The first, an object known as ‘Oumuamua, was discovered back in 2017.
Perhaps the most remarkable thing about 2I/Borisov however is just how unremarkable it actually is.
“This is the first comet known to science that arrived from outside the solar system, and it is completely similar to those we see inside the solar system,” said astronomer Michal Drahus.
Its discovery suggests that there are several nearby solar systems very much like our own and that comets like those we find in our local neighborhood are not uncommon elsewhere in the universe.
Observations using the William Herschel Telescope on La Palma, Spain and the Gemini North telescope on Mauna Kea, Hawaii have shown that 2I/Borisov has a distinctive and familiar coma (a billowing cloud of gas and dust) as well as a short, fat tail.
Its nucleus is thought to be 2km wide .
“This appears to be a completely unremarkable comet on a very remarkable orbit,” said astronomer Colin Snodgrass from Edinburgh University.
“It’s very interesting that this interstellar comet looks like our own ones.”
“It implies that some of the formation processes we are trying to figure out with detailed observation of comets and asteroids, or space missions like Rosetta, are common between stars.”