Just around two months ago, a cigar-shaped space rock that astronomers say originated from another stellar system came zipping through the solar system. Astronomers gave it the name Oumuamua, and it’s been a hot topic for a while now.
Image Credit: ESO/M. Kornmesser
Experts knew that Oumuamua wasn’t native to our own stellar system because of its eccentric orbital path and surprising velocity, but many questions remain. Fortunately, a new study published in the journal Nature Astronomy this week offers some potential insight.
Considering that Oumuamua didn’t exhibit a comet-like trail when it passed by the Sun, astronomers quickly discounted the “alien comet” theory and went with an “alien asteroid” theory instead.
But what if that wasn’t the case? What if Oumuamua was actually an alien comet in disguise?
Queen's University Belfast, Northern Ireland professor Alan Fitzsimmons, the lead author of the study, cites Oumuamua’s rather peculiar reddish surface color as a potential means of explaining its composition. As it would seem, the details match the profile of a carbon-like protective crust.
It’s possible that Oumuamua might have been a regular-looking comet at one time or another, albeit from another stellar system, but its prolonged exposure to cosmic radiation from interstellar space would have transformed its composition beyond recognition. That said, it all makes sense now why some astronomers might have been quick to call it an asteroid.
Furthermore, there might still be ice at the core. If the carbon-like crust had a thickness of at least 20 inches or more, then it would have been sufficiently-insulated from the Sun’s heat and prevented any visible trails from occurring.
Fitzsimmons admits how these theories are merely hypothetical based on the limited data available, but they’re some of the most plausible ideas yet. Unfortunately, Oumuamua didn’t stay around long enough for detailed observations, and it’s already leaving our stellar neighborhood.
At this point, our only hope for solving the mystery behind alien space rocks of this nature is for another Oumuamua-like object to fly through the solar system in the future. Ensuing observations with powerful space telescopes like the upcoming James Webb Space Telescope might validate or discredit the current theories and propel our understanding of the universe around us.