Interstellar asteroid Oumuamua
ESO / M. Kornmesser
Experts at Harvard University have recognized the probable version according to which the interstellar asteroid Oumuamua is a space sail — an alien probe that accelerates using the pressure of solar wind ions. However, the acceleration of the asteroid can be explained by natural causes.
Oumuamua is a cigar-shaped asteroid 400 meters long and about 30 meters in diameter. It was discovered on October 19, 2017 at a distance of 0.2 astronomical units from the Earth (a quarter of the distance between the Sun and the Earth). When the object left the solar system, its speed suddenly increased, which surprised astronomers.
The most likely explanation for the change in speed was degassing, caused by the heat from the sun. However, this process was not observed when the object was closer to the Sun.
According to the new hypothesis, Oumuamua sped up due to the pressure of sunlight.
According to astrophysics from the University of Queens Alan Fitzsimmons, the observed properties of the asteroid are consistent with the behavior of comet-like bodies ejected from another planetary system, reports Phys.org.