Oumuamua interstellar object spent billions of years in chaos over violent past

The Oumuamua interstellar object has been tumbling through space for billions of years due to a violent past, according to researchers with Queen's University Belfast. The object was first announced late last year; it has the distinction of being the first (known) interstellar object to visit our solar system, though it was shrouded in mystery. Much of that mystery remains, but researchers are beginning to unravel it.

Researchers first spotted the interstellar object back in October, first believing it to be a comet. Upon further evaluation, experts realized Oumuamua is an asteroid, one with an unusual, elongated shape. Scientists with Queen's University Belfast and colleagues around the world have been studying the object since.

Unlike other asteroids, Oumuamua was found to have a chaotic spin as it hurtled through space, this compared to other small asteroids which simply spin periodically. According to Dr. Wes Fraser, this may be due to an impact with a different asteroid in its own system, which knocked it into interstellar space and caused it to start tumbling in an unusual way.

Dr. Fraser went on to explain, "Our modeling of this body suggests the tumbling will last for many billions of years to hundreds of billions of years before internal stresses cause it to rotate normally again." Fraser's research also points toward a potentially odd composition.

While the asteroid's body is described as having a mostly neutral color, the long face portion of it is mostly red, which accounts for color variations found during measurements. "This argues for broad compositional variations," Dr. Fraser says, "which is unusual for such a small body."

SOURCE: Queen's University Belfast