A dwarf planet recently discovered at the far edge or our solar system adds evidence for the existence of a much larger body, possibly ten times the size of Earth, orbiting far from the sun but still in our solar system.
If astronomers can track it down, we could become a nine-planet solar system once again.
The planet is theoretical for now, inferred from the influence it seems to have on this new dwarf planet and others in its vicinity.
The discovery of the dwarf planet was published in the journal Nature Wednesday by astronomers Scott Sheppard of the Carnegie Institution for Science and Chad Trujillo of Gemini Observatory.
They report the detection and verification of a dwarf planet provisionally named 2012VP113 and jokingly called “Biden” because of its “VP” initials.
It is the farthest orbiting object ever detected, beating out Sedna, found in 2003 by a team led by Mike Brown of Caltech, which included Trujillo.
“Biden” was located in a region known as the inner Oort Cloud, far from the sun. This object is 80 times farther from the sun than the Earth is — and that’s at it closest point. It then goes on an orbit so long that it is hundreds of Earth distances away.
Sedna, closer in to the sun, takes 11,400 Earth years to complete its orbit.
Sheppard called the orbit of “Biden” “very stable, but eccentric.”
What’s most interesting to the astronomers is that previously found objects and some they have since discovered are equally eccentric.
They point to the influence of a giant planet that perturbed the orbits of the objects being found and then either flew off into space — or is still hiding out there somewhere.
“The evidence for it is circumstantial,” said Sheppard, in a phone interview from Chile where he is observing again on the Blanco DECam at the Cerro Tololo International Observatory.
“We’re continuing the story, he said. We have several new candidates that we’re following up.”
The objects are very far away and very faint, he said, which is why they are so difficult to detect.
The discovery is good news for the Tucson-based National Optical Astronomy Observatory, whose newly retrofitted 4-meter Blanco Telescope in Chile was used to find the newest member of our solar system.
Read more about the discovery and the technology that allowed it in tomorrow's Arizona Daily Star.