In August, Ukrainian skywatcher Gennady Borisov sighted what is believed to be the second interstellar comet known as C/2019 or Borisov. While Borisov is being touted to be the first travelling successor to the interstellar object Oumuamua, scientists finally seem to have figured out where Borisov exactly came from.
According to experts, Borisov’s history dates back to one million years, when it passed a binary star system called Kruger 60. A new study by astronomers from the A. Mickiewicz University in Poznań, Poland, and the Space Research Centre of the Polish Academy of Sciences suggests that the new interstellar comet found likely came from the double red dwarf, somewhere from the zone the Cepheus constellation.
For starters, Kruger 60 is a visual binary stellar system currently only 13.15 light-years from the Sun and approaching. It was discovered in 1873 is the tenth closest multiple stellar system. Kruger 60 consists of two M-type stars (red dwarfs) – Kruger A and Kruger B, that orbit each other once every 44.6 years.
While trying to trace the origin of Comet Borisov, researchers at the Polish university found that Kruger 60 is a good candidate for a home system of 21/Borisov. To test their theory, the astronomer analyzed 548 observations of the interstellar comet available from the Minor Planet Center at the International Astronomical Union. In addition to that, they modeled the comet, the Sun and 647 stellar systems from their list of potential perturbers of cometary motion.
The results? They found that 21/Borisov zipped past Kruger 60 at a distance of 5.7 light-years having an extremely small relative velocity of 3.43 kilometres per second. Dr. Piotr Dybczynski from the A. Mickiewicz University writes in the research, “As the orbit of this comet will become more precise the minimal distance between these two bodies might vary but their relative velocity will remain very small, which suggests that 2I/Borisov might originate from Kruger 60.”
Cover Credit: NASA