© G. Bacon, STScI/NASAArtist's conception of a small icy object beyond Pluto (file picture).
An as yet undiscovered planet might be orbiting at the dark fringes of the solar system, according to new research.
Too far out to be easily spotted by telescopes, the potential unseen planet appears to be making its presence felt by disturbing the orbits of so-called Kuiper belt objects, said Rodney Gomes, an astronomer at the
National Observatory of Brazil in Rio de Janeiro.
Kuiper belt objects are small icy bodies - including some dwarf planets - that lie beyond the orbit of Neptune.
Once considered the ninth planet in our system, the dwarf planet Pluto, for example, is one of the largest Kuiper belt objects, at about 1,400 miles (2,300 kilometers) wide. Dozens of the other objects are hundreds of miles across, and more are being discovered every year.
What's intriguing, Gomes said, is that, according to his new calculations,
about a half dozen Kuiper belt objects - including the remote body known as Sedna - are in strange orbits compared to where they should be, based on existing solar system models.The objects' unexpected orbits have a few possible explanations, said Gomes, who presented his findings Tuesday at a meeting of the
American Astronomical Society in Timberline Lodge, Oregon.
"But I think the easiest one is a planetary-mass solar companion" - a planet that orbits very far out from the sun but that's massive enough to be having gravitational effects on Kuiper belt objects.
Mystery Planet a Captured Rogue?For the new work, Gomes analyzed the orbits of 92 Kuiper belt objects, then compared his results to computer models of how the bodies should be distributed, with and without an additional planet.
If there's no distant world, Gomes concludes, the models don't produce the highly elongated orbits we see for six of the objects.
How big exactly the planetary body might be isn't clear, but there are a lot of possibilities, Gomes added.
Based on his calculations, Gomes thinks a Neptune-size world, about four times bigger than Earth, orbiting 140 billion miles (225 billion kilometers) away from the sun - about 1,500 times farther than Earth - would do the trick.
But so would a Mars-size object - roughly half Earth's size - in a highly elongated orbit that would occasionally bring the body sweeping to within 5 billion miles (8 billion kilometers) of the sun.
Gomes speculates that the mystery object could be a rogue planet that was kicked out of its own star system and later captured by the sun's gravity.
Or the putative planet could have formed closer to our sun, only to be cast outward by gravitational encounters with other planets.
However, actually finding such a world would be a challenge.
To begin with, the planet might be pretty dim. Also, Gomes's simulations don't give astronomers any clue as to where to point their telescopes - "it can be anywhere," he said.
No Smoking GunOther astronomers are intrigued but say they'll want a lot more proof before they're willing to agree that the solar system - again - has nine planets.
"Obviously, finding another planet in the solar system is a big deal," said
Rory Barnes, an astronomer at the University of Washington. But, he added, "I don't think he really has any evidence that suggests it is out there."
Instead, he added, Gomes "has laid out a way to determine how such a planet could sculpt parts of our solar system. So while, yes, the evidence doesn't exist yet, I thought the bigger point was that he showed us that there are ways to find that evidence."
Douglas Hamilton, an astronomer from the University of Maryland, agrees that the new findings are far from definitive.
"What he showed in his probability arguments is that it's slightly more likely. He doesn't have a smoking gun yet."
And
Hal Levison, an astronomer at the Southwest Research Institute in Boulder, Colorado, says he isn't sure what to make of Gomes's finding.
"It seems surprising to me that a [solar] companion as small as Neptune could have the effect he sees," Levison said.
But "I know Rodney, and I'm sure he did the calculations right."
Reader Comments
That's pretty good for a story like this!
It'll be interesting to see how it plays out.
How knows, mayby Neptune was a star in distance past and will light up again one day and we will have two suns.
Well both have about same composition 80% of hydrogen and 20 % helium.
I kind of belive in old myths and mix of todays knowledge, so hopi prophecy with blue star is something I kind of waiting for. Here is some links to Sedna (mythology) [Link], and sedna as trans-Neptunian object [Link]Cheers
Theories arise. Some proven, some kept, and some tossed on the shelf. What of the WISE infrared telescope? Release of the WISE All-Sky data to the scientific community was on March 14,2012.
It is going take some time but I have a feeling there are computer programs that decipher distance and types of objects within any given distance when an image from WISE is inputted for study. How exhilarating that must be to be the first to see an object that may be heading into our solar system or to see something never seen before.
This rogue planet could be a runaway or an outer orbit object in a theorized Binary star system. Neptune's wobble has always been a wonder for scientists. What causes it's odd tugging?
I recently read about G1.9 + 0.3 ,a Super Nova Remnant...so they claim.
"The discovery that G1.9+0.3 had been identified as the youngest known Galactic SNR was announced on May 14, 2008 at a NASA press conference. In the days leading up to the announcement, NASA would only hint that they were going "to announce the discovery of an object in our Galaxy astronomers have been hunting for more than 50 years." wikipedia.
"Besides being the record holder for youngest supernova, the object is of considerable interest for other reasons. The high expansion velocities and extreme particle energies that have been generated are unprecedented and should stimulate deeper studies of the object with Chandra and the Very Large Array." [Link]
"G1.9+0.3 is the only Galactic SNR increasing in flux, with implications for the physics of electron acceleration in shock waves." [Link]
Fascinating, as Spock would say.
It takes 248 years for Pluto to orbit the Sun. How long would it take for an outer object of another solar system to orbit it's parent star...and to come into proximity with our outer planets orbits? Neptune could be way on the other side of the Sun while a Binary System's outer planet could be at a position that would have caused many perturbing woes if Neptune happened to be crossing it's path. It is all about timing I suppose. A very long timing, kind of like a Trojan asteroid interacting a Earth orbital crossing. We just need to find our Binary Star, A Brown Dwarf? A White Dwarf, A Y Dwarf (A newly discovered type of cool star)? Is this the Son of God, an allegory perhaps? To return in 2000 years? 2012? The days of antiquity were entertained by the night skies. The human conscious must have been filled with amazement at celestial wonders. Watch the film Zeitgeist sometime and put on headphones and listen to it's philosophy and reasoning, To weigh and consider: [Link]
We have been given cake for a long time to keep us distracted. How ironic that Kiersten Dunst plays both Marie Antoinette ("Let them Eat Cake") and Justine in Melancholia, a haunting film with a Runaway Planet.
I have an art commission to make. I have no time for this Melancholia. Space, the final frontier will have to wait.