Astronomers found oxygen in images of the first interstellar comet 2I/Borisov.

This may indicate that there is water on the 2I/Borisov comet.

An Interstellar Comet 2019 Comet Borisov picture
An Interstellar Comet 2019 Comet Borisov

An article describing the work on comet 2I/Borisov comet has been published on

Comets are relatively small celestial bodies that consist of solid particles and ice. All previously known comets belonged exclusively to the solar system: they moved around our sun in a very elongated orbit.

However, in August 2019, the Crimean astronomer Gennady Borisov discovered an object that was moving in a very unusual orbit. Subsequently, it turned out that this was the first interstellar comet, that is, it arrived from outside the solar system. 

In mid-September, the International Astronomical Union officially named the celestial body after the discoverer, 2I/Borisov.

According to the latest estimates of astronomers, the diameter of the comet's core is about 1 km. Borisov comet is in reddish color, which may indicate the presence of organic matter in the depths of the comet, and is covered with a large amount of dust. 

Earlier, astronomers had already found traces of cyanide gas on the comet, and new observations showed that there were other substances on the comet.

The comet's water plume, comet 2I/Borisov.

With the help of the ACRES instrument of the Apache-Point Observatory, astronomers received new high-quality images of the comet's spectrum. Scientists saw in them a line that corresponds to oxygen. As experts suggest, this may mean that the comet may have water on it.

Preliminary estimates suggest that 2I/Borisov comet water quantity can be either the same as the average water on solar comets or slightly more. The dust-to-gas ratio of the Borisov comet corresponds to the average values for similar objects in our solar system.

In general, new data confirmed the previous conclusions of astronomers that Borisov comet does not differ much from similar objects of the Solar System. 

comet 2I/Borisov in the solar system
comet 2I/Borisov.

In early December (presumably on the 8th) it will approach the Sun at a minimum distance. It will be impossible to see it with the naked eye, but at the end of 2019 (about December 29) it may be possible to see it with amateur telescopes. 

Observations will help to learn more about the composition and other characteristics of the interstellar comet.