'Interstellar guests' in the Solar System

Oumuamua is the first interstellar asteroid to fly over the recorded Solar System. However, the latest research shows that in our planetary system there may be many asteroids coming from other star systems.

Fathi Namouni scientists at the Côte d'Azur Observatory (France) and Helene Morais at the University of Sao Paulo (Brazil) discovered 19 objects thought to be from other planetary systems. This fact proves that interstellar objects in the Solar System may not be as rare as the original assumption. 

Studies on this topic are published in the journal 'Monthly Notices of the Royal Astronomical Society' (UK).

Interstellar objects

Astronomers claim that Oumuamua is neither the first nor the last 'guest' in the Solar System. Recent studies show that there is a whole population of objects born from nearby stars. 

Comet 2I / Borysov.

The scientists identified 19 interstellar objects by observing how they moved around the Sun. According to them, these objects come from other star systems and fell into the gravitational trap of the Solar System at a time when our planetary system was still very young, only a few million years old.

Namouni and Morais used computers to simulate the orbital evolution of outer Neptune (Kuiper belt objects - KBO) and objects called centaurs ( micro-planets ) rotating in orbit. Jupiter and Neptune. 

All 19 interstellar objects have an inclined orbit (some also have a nearly perpendicular orbit) compared to the planets' orbital planes.

One of these interstellar objects - the asteroid Ka 'epaoka' awela, orbits in a similar orbit to Jupiter, but in the opposite direction.

Observing interstellar objects, Namouni and Morais came to the conclusion that if they were from the Solar System, they would have to move in orbit in the same direction as all other celestial bodies. However, in reality it is not so.

Cradle made stars

The scientists analyzed 17 centaurs with orbital angles greater than 60 degrees and two objects orbiting outside Neptune orbit, the KBO celestial body. 

They used known data on the orbits of these objects to create multiple orbital versions for each object, for the purpose of observing on computer simulations that these orbits could change over time such as how, from the beginning of the universe (4.5 billion years ago). 

Reverse movement of the asteroid Kaʻepaokaʻawela.

At that time, our Solar System looked completely different than now. All celestial bodies lie on a relatively flat disk, orbiting the young Sun (the Sun was still in the cradle of stars - where stars formed in the vicinity of a cloud of gas and dust). 

' The proximity to other stars means that the gravitational field is much stronger then today. As a result, asteroids can be moved from one star system to the second , ' explains Namouni.

Thus, all that is born in the accretion disk of the young star must rotate in the same plane and in the same direction. 

However, 19 interstellar objects did not follow this rule. Simulations of the asteroid Ka 'epaoka' awela show that the asteroid's orbit began as interstellar space and the asteroid itself was captured by the Solar System 4.5 billion years ago. . 

Scientists Namouni and Morais claim that the objects they studied may have been 'imprisoned' by the gravitational field of the Sun , rather than they were born in the Solar System. 

The two scientists also believe that there are many such interstellar objects. Some objects fall near the sun; others were thrown out of the solar system.

If these objects are indeed formed around other stars, then they carry great scientific value. 

Their similar and different characteristics compared to the asteroids born in the Solar System can tell us more about the formation of the Solar System and other planetary systems.

'The discovery of asteroid populations of interstellar origin is an important step in identifying the physicochemical characteristics similar and different between asteroids born in the Solar System and in interstellar space. 

This population gives us guidance on the subject of the constellation, where the Sun was formed, how to capture interstellar asteroids and the role of interstellar matter in shaping the evolution of the Solar System ' - scientist Helene Morais explained.