Interstellar object, thought to be alien probe, turns out a familiar object; Oumuamua didn't

The study report suggested that interstellar visitor Borisov was not an unusual visitor to Earth as it has a well-defined tail, a classic characteristic of comets

Interstellar comet
The first color image of the comet C/2019 Q4 (Borisov), was captured by the Gemini North telescope at Hawaii's Mauna Kea. Gemini North acquired four 60-second exposures in two color bands (red and green). The blue and red lines are background stars moving in the background. Gemini Observatory/NSF/AURA/Travis Rector

It was in 2017 that humans first detected 'Oumuamua', an interstellar visitor that reached the solar system from deep space. The arrival of Oumuamua sparked debate among the scientific community, as many space experts including Avi Loeb of Harvard University suggested that this interstellar visitor could be an alien probe. However, most of the space experts dismissed the claims of Loeb. They made it clear that this interstellar visitor is most probably an asteroid.

A few weeks back, Gennady Borisov, an amateur astronomer, discovered a second interstellar object that reached the solar system. Scientists named this interstellar body 'C/2019 Q4' (Borisov), and now, a new study has revealed that this second interstellar visitor is a surprisingly familiar object.

It should be noted that scientists have been anticipating the arrival of an interstellar object for years. But the first interstellar visitor 'Oumuamua' went against all expectations. Oumuamua was an asteroid rather than a comet, and it did not have a tail.

However, the second interstellar object 'C/2019 Q4' seems much more in line with human expectations and, being a comet, it has a defined tail.

"Oumuamua looked like an asteroid, but Borisov is a comet—it has a long, defined tail and a coma around the middle. This is important because many have speculated that interstellar space should be occupied mostly by comets," Michal Drahus, an astronomer at the Jagiellonian University in Poland and the lead author of the study told Gizmodo.

The study report published in the journal Nature Astronomy also revealed that the elemental composition of Oumuamua and Borisov is different.

It should be noted that Borisov comet was discovered during its inbound approach, and it will give scientists more time to study this interstellar visitor. Experts believe that this comet may make a close approach with the earth soon, and it will help to know about interstellar visitors that reach the solar system.