Watch out Pluto, you’ve got some competition.

University astronomers and physicists, in collaboration with the California Institute of Technology and the Gemini Observatory, have discovered what they claim is the 10th planet, taking Pluto’s status as farthest planet from the Sun.

“If this one isn’t a planet, then neither is Pluto, which means it may be demoted,” joked physics professor Charles Baltay, the leader of the Yale-based team.

The new planet, which for now is called 2003 UB313, is larger than Pluto and is currently about 100 times farther from the sun than the Earth. It was spotted using what physics professor David Rabinowitz calls the world’s largest area detector camera, which was built at the University.

“If you want to find a bigger mouse, you have to build a bigger mouse trap,” Baltay said.

2003 UB313 was found lurking in the depths of space in the Kuiper Belt — the ring of asteroid-type rocks that circle in orbit beyond Neptune’s path. Rabinowitz said this new planet is potentially a second “kingpin” in the Belt, the other being Pluto.

For now, all that is known about 2003 UB313 is that it is slightly larger than Pluto and has an icy surface. But the first fact alone is sufficient to validate it as a new planet. Future goals include determining the composition of the planet and its atmosphere and whether or not it has any satellites, Brown said.

Although Pluto will not be the last planet, it may be the last named after a male figure.

“Maybe we’ll name this one after a Greek goddess to keep up with the times,” Baltay said.

The undertaking, named the Quest Project, is the result of continued efforts by Baltay and Rabinowitz’s team. The Quest Project has ten different objectives within it, one of which is searching for new planets. Others include examining the skies to find supernovae and determining the age of the universe.

The area detector camera carries out full-sky surveys which are then delivered electronically the following morning to Rabinowitz, California Institute of Technology planetary science professor Mark Brown and Chad Trujillo of Gemini Observatory in Hilo, Hawaii.

The discovery was made using the high-powered telescope at Palomar Observatory, nestled in the mountains of northern San Diego County. The Palomar telescope is operated by Caltech.

“Basically the deal was that if we built the huge camera, then we could use the telescope,” Rabinowitz said.

Prior to the Palomar telescope, the Yale team used the National Telescope in Venezuela, a much smaller and less powerful piece of equipment. The Venezuelan astronomers were still using photographic plates and developing them to look at images of the nighttime sky, an antiquated method, Baltay said.

While astronomers working in New Haven were analyzing images from Venezuela, astronomers at Caltech were brewing up a galactical storm of their own in Pasadena.

“I’ve been searching for this stuff ever since day one when I was a grad student at Berkeley,” Brown said.

Collaboration between the University and Caltech has grown since 2003, when the schools agreed that Yale scientists would provide their camera to make the powerful Palomar telescope even more potent.

Now, in conjunction with the Gemini Observatory, Brown said the two have succeeded at something astronomers have attempted since the days of Gallileo — discovering a new planet.

“Nothing this large has been discovered in space since 1846 when Neptune was discovered,” he said, “And that is one of the most exciting aspects to this event.”

Yale astronomers agreed that this collaboration works well due to the location of the Palomar telescope.

“Turns out it rains quite a bit in Venezuela,” Baltay said. “Of course, we are beginning to see more and more light pollution at Palomar because of nearby cities San Diego and Los Angeles.”

In order to continue finding new planets, Baltay said a search based somewhere other than on Earth may be necessary. Telescopes such as the space-based Hubble telescope, which gives clear images of detailed smaller areas much further out in space, allow astronomers like the Quest team to locate even bigger things than 2003 UB313, he said.

When a land telescope such as the Palomar is used, the field of vision is blocked by atmospheric gases and the earth’s environment, Baltay said. Going directly to space would eliminate that blockage.