Have they found ‘Planet X’? Not very likely . . .

Fellow astronomers blast reports of possible planets in outer reaches of solar system

It’s a big, dark presence at the farthest reaches of our solar system, a mysterious force powerful enough to skew the paths of planets in orbit and yet so subtle that it slips undetected past even the most powerful telescopes on Earth. For centuries, it has eluded some of the most brilliant minds in astronomy — some say it even destroyed one. It’s the subject of endless calculations and rampant speculation, crackpot theories and countless hours spent gazing, fruitlessly, at the night sky. It’s known as Planet X. And last Tuesday, a group of astronomers said they’d found not just one such presence, but two of them.

Using the Atacama Large Millimeter/submillimeter Array (ALMA), a powerful telescope located in the high desert of Chile, the researchers said they’d come across two extremely large objects skimming through the outskirts of the solar system.

“ALMA discovers the most distant object of the solar system,” read the title of one paper uploaded to the research-sharing site arXiv. “The serendipitous discovery of a possible new solar system object with ALMA,” went the other.

Though both studies were submitted to the prestigious journal Astronomy & Astrophysics, neither has been peer-reviewed or formally published — steps that are par for the course with any kind of serious scientific research but especially when pronouncements of previously unknown planets are at stake. They’re both based on limited observations — just two spottings apiece for each odd object. And even after just 48 hours online, they have garnered a great deal of skepticism within the astronomy community.

But the researchers say they posted their papers with exactly that purpose. “We specifically wanted to reach the community that could tell us if we overlooked something, in which case we fully intend to withdraw the papers,” Wouter Vlem- mings, an astronomer at Chalmers University of Technology in Sweden and co-author on both studies, told Scientific American.

Here’s what Vlemmings and his colleague say they found:

A large rocky something they call “Gna” (for a fast-moving Nordic messenger goddess, one of the authors told Scientific American), which could be an asteroid-type object roughly the size of Ireland zooming around somewhere near Uranus. Alternatively, the researchers propose, it could be an undiscovered planet floating much farther out, or even a brown dwarf (bigger than a planet, smaller than a star) passing through interstellar space.

Also, a mysterious, unnamed object that appears in the sky close to the Alpha Centauri system that may be a “Super-Earth” planet far beyond even Pluto or a brown dwarf that’s really far. It could also conceivably be an icy “trans-Neptunian object,” of which there are plenty in the frozen darkness past the eighth planet, but the researchers say that’s less likely (it’s also less interesting).

All of which sounds pretty cool — unless you’re Mike Brown, a Cal Tech astronomer who has spent the majority of his career scanning the farthest reaches of the solar system for just these kinds of objects.

Brown, the self-proclaimed “Pluto killer” who discovered a trans-Neptunian object that helped dethrone the erstwhile ninth planet back in 2005, would be thrilled to find the long-sought Planet X. He’d be almost as happy to see a paper reporting that other researchers had found it.

But these two papers, he said, are not that.

“The logical leaps are sort of astounding,” he said. “What they really say they saw is a little blip and then six months later another little blip.”

The evidence that the researchers offer for their findings is too scanty, Brown said, and the probability that they could have stumbled across a huge, planet-like object in a tiny patch of sky is too small. Finding Planet X in the small field of vision they studied with the ALMA telescope, he said, “would be like scooping a cup full of water from the ocean and pulling out the white whale.”