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Astronomers Believe They’ve Found a New Object in Our Solar System Beyond Neptune and Pluto

Move over, Pluto.


It seems that we hear about a new “super Earth” or other exoplanet discovered just about every day, but those are all well outside of our solar system in the distant reaches of space. Finding an object within our own stellar neighborhood would be a much rarer occurrence, and some astronomers now believe they’ve done just that.

Of course, that doesn’t mean it’s a sure thing at this point. The object, discovered in data from Atacama Large Millimeter/submillimeter Array (ALMA), has only been recorded in 2014 and 2015 due to the small amount of sky ALMA observes at any give time, and it’s hard to say exactly what we’re seeing without more data. On top of that, its distance and its size are both up for debate due to that lack of information, meaning it could be very large and very far away or much smaller and much closer.

Still, two teams of astronomers have submitted papers (not peer-reviewed yet) claiming that the object is a massive body within our solar system based on its movement and maybe even another planet. The object was spotted while looking in the direction of Alpha Centauri, a binary star system that’s our Sun’s closest neighbor. It could be a part of that system, as Alpha Centauri’s proximity to Earth also causes it to appear to move in relation to other stars, but if it were another star, the object should have been noticed before, and if not, it’s unlikely we’d see it at all:


image via Liseau, et al.

However, the most likely explanation is probably an icy, less-than-planet-size object out past Neptune and Pluto but closer than if it were another planet. There may well be tons of large (yet still smaller than Pluto) icy objects out there, which would make it seem far more likely to see one when looking at a random patch of sky. Larger (physically larger) possibilities brought up by the astronomers, like a “super Earth” or a cool brown dwarf, if they exist, should be few and far between, making the likelihood that we’ve spotted one by chance fairly low.

However, the teams still believe it’s possible, and it is, but it’s also possible that the object doesn’t exist at all, as others have pointed out. We’ll have to wait for more data on this one, but if this object is really out there, it could be an interesting find.

(via, image via Parée on Flickr)

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Dan Van Winkle (he) is an editor and manager who has been working in digital media since 2013, first at now-defunct Geekosystem (RIP), and then at The Mary Sue starting in 2014, specializing in gaming, science, and technology. Outside of his professional experience, he has been active in video game modding and development as a hobby for many years. He lives in North Carolina with Lisa Brown (his wife) and Liz Lemon (their dog), both of whom are the best, and you will regret challenging him at Smash Bros.