A space object traveling from one planetary system to another sounds incredible, but it can indeed happen. The distances between stars are enormous – for instance, roughly 4.3 light-years separate our own Solar System from Alpha Centauri, meaning the closest planetary system. We would never be able to go there during a human lifetime.
But giving the necessary time that will far exceed how long a human being can live, an asteroid or comet can travel such a distance. According to a new study that Space.com writes about, comets belonging to other solar systems enter ours more often than scientists thought.
The secret could lie in the Oort Cloud
The new study suggests that the Oort Cloud present at the edges of our solar system could be teeming with space objects that have their origin around other stars. The study even implies the assumption that the Oort Cloud could contain more interstellar material than matter created in our own Solar System.
However, the Oort Cloud is still too far away for a spacecraft to go there in the near future. Studying the region is pretty complicated, as the objects from the Oort Cloud are too far away to reflect much of the light from the Sun. Therefore, it seems impossible that scientists were able to figure out that there must be many interstellar objects in the Oort Cloud. But science never ceases to amaze us.
Amir Siraj, who’s a graduate student at the Department of Astronomy of Harvard University, was able to use the discovery of the 2l/Borisov interstellar object to calculate the probability of foreign comets coming to our Solar System, as he explained for Space.com via email.
Siraj said, as quoted by Space.com:
Based on the distance that Borisov was detected at, we estimated the implied local abundance of interstellar comets, just like the abundance of ‘Oumuamua-like objects was calibrated by the detection of ‘Oumuamua.
The 2l/Borisov comet zipped by our planet in late 2019, and it was the second observed interstellar object discovered after ‘Oumuamua.