On August 30 this year, amateur astronomer Gennadi Borisov discovered a comet with a self-made telescope. Several amateurs do this every year and are usually not worth mentioning. But comet Borisov, now named after his discoverer, is literally a godsend for professional astronomers like Gregory Laughlin from Yale University in the USA:
“This object comes from another solar system. Borisov runs on a path on which he only visits the solar system. He is too fast to turn into an orbit. He simply walks past the sun, gets a little distracted and disappears again the Milky Way. So Borisov did not form – like the other comets – together with the Sun, the Earth and the other planets. It comes from another star, but we do not know which of the remaining 100 billion stars in our Milky Way. “
A well traveled visitor
Borisov is an interstellar object, as the experts say. It shows up only once and never again. The astronomers now take every opportunity to point their telescopes at the exclusive guest. These days Borisov comes closest to Earth, but unfortunately remains about 300 million kilometers from the Sun and Earth.
“We will examine exactly what elements are found in the gas envelope and tail of the comet and what its dust is made of. We learn a lot about the conditions under which Borisov was formed change little. That tells us something about the comet’s nucleus, which we cannot observe directly because it is inside the dense gas cloud. “
Where does the comet come from?
Borisov had probably been on the Milky Way for millions of years before he finally found himself in the area of attraction of the sun. But Gregory Laughlin can only speculate about the exact history of the cosmic visitor.
“Borisov must have been thrown out of another solar system – probably from a fairly massive planet that is quite far from its star. With us, Jupiter, Saturn, Uranus and Neptune could kick comets out – planets like our Earth cannot. We already know thousands of planets with strange stars, but they mostly run on very narrow orbits and could not send a comet on the journey. Borisov therefore indicates that there are many previously undiscovered massive planets in other solar systems. “
A “care package” from another planetary system
This also speaks for the fact that Borisov is now the second interstellar object within two years. In 2017 ‘Oumuamua was drawn through the solar system. While some experts are working on space probes for trips to distant stars, nature literally comes towards them. Research on interstellar objects has only just begun, says Gregory Laughlin:
“We get ‘care packages’ from other planetary systems! With new large telescopes such as the Large Synoptic Survey Telescope LSST, which will go into operation in a few years, we will discover many, many more of these interstellar visitors. And if we find an object like Borisov in time we could send out a spacecraft that takes pictures up close or even takes material samples as it flies close to the sun. It’s going to be very, very exciting. “
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