Interstellar objects may disappear before they get close to Earth

Although astronomers estimate that there are many interstellar objects “walking” around our solar system, only two have been identified so far: o Oumuamua and the guilty 2 I / Borisov. It’s just that, in addition to being difficult to find, they may not survive long enough to get close to the ground.

according to new search, interstellar objects can be eroded by cosmic rays – atomic nuclei, made up of protons and neutrons, traveling in space at speeds close to the speed of light. If true, ‘Oumuamua’ was probably much larger when it began its journey through the Milky Way.

Four types of ice were analyzed: nitrogen (N2), carbon monoxide (CO), carbon dioxide (CO2) and methane (CH4). The study authors sought to discover whether these types of space objects could survive cosmic rays in the interstellar medium. They also looked at erosion caused by collisions between objects and the surrounding gas.

In addition to these elements that objects encounter along the way, there are other variables, such as the flux and strength of cosmic rays, that can determine how much erosion will occur on icy rock. Likewise, surrounding gas can also travel in varying flows, with varying intensity and strength, resulting in different rates of object degradation. Finally, each type of ice erodes at a different rate.

Nitrogen ice is an important topic of study in this line of research, as astronomers suspect that Oumuamua was just a massive piece of N2 ice, torn from a Pluto-like planet in a star system far from Earth. If so. The original size of this visitor would be between 10-50 km. The 40 km interval shows the degree of uncertainty because we do not know the strength and flux of cosmic rays that Oumuamua encountered on his journey.

With this little information and some assumptions about the origin of things, researchers can infer other things, such as how far ‘Oumuamua has traveled. If the mechanisms of formation of interstellar objects inform the initial radius of the object, then it is possible to determine the distance of their origins based on the velocity of the object.

Far from being conclusive, the study suggests research to expand knowledge about cosmic rays, which appear to be a critical factor in the survival of interstellar objects, and also to determine their origins if we encounter other visitors from distant stars. It’s estimated that there are billions of them traveling through our galaxy, so it’s only a matter of time to find more.

Source: ScienceAlert