Scientists discovered that the first interstellar object that visited the Solar System in October last year had a violent past that is causing it to tumble and spin around chaotically.
The findings of the study published in the journal Nature Astronomy on February 9 indicate that the cigar-shaped asteroid had collided with another asteroid in the past. Scientists from the Queen’s University Belfast in Northern Ireland led the discovery and research, according to Phys. Org.
The scientists found that Oumuamua was not spinning periodically like most asteroids and objects seen in the Solar System. They discovered that Oumuamua has been tumbling or spinning chaotically, probably for billions of years.
Wes Fraser, one of the authors of the study from Queen’s University Belfast’s School of Mathematics and Physics, said that Oumuamua’s erratic motion might be a result of a collision with another asteroid. He further noted that the tumbling could have been caused by an impact with another planetesimal in its system before it ejected into interstellar space. He also said that their modeling of this interstellar object indicates the tumbling will last for many billions of years to hundreds of billions of years before internal stresses cause it to rotate usually again.
Something Violent Happened to Our Solar System's First Interstellar Visitor – An interstellar object called 'Oumuamua has confounded astronomers ever since it passed through our solar system in October of last year. https://t.co/g7zewAV4x0
— Slurp News (@SlurpNews) February 14, 2018
Another strange thing that the scientists discovered is that Oumuamua varied in color. They could not figure it out at first. However, the scientists concluded that it had a large red spot on its longer side besides its surface, and the majority of it was the color of dirty snow, according to Live Science.
Dr. Fraser said that most of the surface reflects neutrality, but one of its long faces has a sizeable red region. He further noted that this argues for wide compositional variations, which is unusual for such a small body. He added that Oumuamua is quite rare compared to most asteroids and comets in the Solar System.
Oumuamua passed through the Solar System in October 2017. The interstellar object discovered by Robert Weryk using the Pan-STARRS telescope in Hawaii is about 230 by 35 meters or 800 ft x 100 ft in size. It is reclassified as an asteroid and was approximately 33,000,000 km from Earth the first time it approached. It is a metal-rich rock with a relatively high density, according to some scientists.