The solar system is surrounded by "interstellar rivers."

The asteroid Oumuamua, the comet Borisov, and other visitors from interstellar space have raised numerous questions. Where do they come from? How did they leave their systems and make their way to us? How many more are wandering around the Solar System? Astronomers have concluded that as each star moves through the galaxy, it leaves behind a long trail of lost asteroids. This suggests that the Sun frequently encounters such streams, meaning we can expect many encounters with these extraordinary celestial objects.

2024-11-30 10:01:14https://naked-science.ru/article/astronomy/solnechnaya-sistema-okaza

The interstellar object 'Oumuamua', discovered in 2017, was primarily identified by its trajectory: the asteroid traveled along a massive hyperbola, at a steep angle to the plane of rotation that most of the Solar System's "population" adheres to. Additionally, it was moving faster than the "local" asteroids, racing past the Sun at a speed of 87 kilometers per second.

Two years later, the first known interstellar comet, Borisov, was found based on similar characteristics. Subsequently, scientists began reviewing archival data and discovered that back in 2014, the interstellar object CNEOS14 not only appeared but also fell into the Pacific Ocean.

Now astronomers are almost certain that such messengers from afar are continuously arriving, but we have only recently learned to detect them. Therefore, it’s intriguing to understand how they leave their home systems and start wandering through interstellar space. Recently, researchers from New Zealand, the UK, the Netherlands, and the USA shared insights on their fate. They provided their calculations in an article available on the preprint server arXiv.org. According to the scientists, such objects are a result of the natural life cycle of stellar systems.

Astronomers operate under the long-held assumption that the Solar System is surrounded by a giant sphere mainly composed of icy bodies — the hypothetical Oort Cloud. If this is the case, one could expect that similar spheres should surround other stars. As they orbit around the center of the Galaxy, a number of small celestial bodies may "get lost along the way." Eventually, these objects begin to move independently around the galactic center, stretching into long cosmic "rivers."

As the researchers emphasized, each such stream should actually contain roughly as many celestial bodies as pebbles in a hundred-kilometer riverbed. Computer simulations have shown that the Solar System may encounter about a million branched streams of interstellar asteroids. Interestingly, when meeting new extrasolar objects, it may even be possible to compare the characteristics of their behavior and thus recognize "brothers," meaning those that once belonged to the same star or star cluster.