'Oumuamua Interstellar Space Object Isn't An Asteroid After All

Remember the 'Oumuamua space object? The mysterious rock appeared late last year, confusing researchers who weren't quite sure what it was. That kicked off months of investigation, slowly revealing details about the rock and its potential origins. Many have referred to 'Oumuamua as an asteroid, but a new study has something else to say on the matter. Turns out, 'Oumuamua is actually a comet.

Despite initial hopes from certain pockets of the popular, 'Oumuamua hasn't turned out to be an alien space ship. Earlier this year, a report suggested that the space rock may originate from a binary system, having been launched into space due to a "violent past." A two-star system is the most likely origins for the rock, but it's possible it instead came from a one-star system.

A study newly published in the journal Nature reveals that 'Oumuamua is most likely a comet, and that's due to an observation that it was experiencing non-gravitational acceleration. "The motion of all celestial bodies is governed mostly by gravity, but the trajectories of comets can also be affected by non-gravitational forces due to cometary outgassing," the researchers explained.

The interstellar rock has an unusual cigar-like shape and is observed tumbling through space. That, coupled with other things, caused a big mystery surrounding the rock's identity, but it turns out 'Oumuamua is just unusual — at least as far as comets are concerned. The comet's outer surface is covered with a layer that may be inhibiting the dust typically observed with comets.

SOURCE: Nature