“Xena,” debated to be the 10th planet of the solar system, apparently has a sidekick – a moon.Astronomers at the Keck Observatory on the Mauna Kea Volcano in Hawaii found the moon, dubbed “Gabrielle” for Xena’s fellow heroine of the TV show “Xena: Warrior Princess,” after taking images of the planet with an advanced telescope, according to the Web site of “Xena’s” discoverer, Mike Brown.

According to Brown’s Web site, the planet currently under debate, 2003 UB313, is being referred to by its nickname, “Xena,” until its official name is decided by the International Astronomical Union.

A moon may help scientists learn more about the planet itself, said Dr. Mike Fanelli, an astronomy instructor in the department of physics and astronomy.

“If it has a moon, it helps us determine the mass of an object,” Fanelli said. “The current estimate is that it’s larger than Pluto.”

Fanelli said it was discovered in 2003, but made publicly known in spring of 2005, after scientists had time to study its orbit.

According to Brown’s Web site, the grayish planet is estimated to be 10 billion miles from the sun, with a 560-year orbit.

Dr. Doug Ingram, an instructor in the physics and astronomy department, said “Xena” may not be a planet, even though it has an object orbiting it.

“The fact that it’s big and has a moon, that may affect the public’s view, but not science’s view,” Ingram said.

“Xena” is located in the Kuiper Belt outside of Neptune’s orbit, an area containing several comets and asteroids, or big balls of ice and large rocks, which also have objects orbiting them, Ingram said.

Ingram said “Xena,” along with Pluto, a planet made up of rock and ice, may not be planets at all.

“Most astronomers agree Pluto would be better classified as a comet because that’s what comets are, big balls of ice,” he said.

Fanelli said generally asteroids do not receive the status of a planet because of their smaller sizes.

“I guess the decision was that these aren’t big objects, so we won’t distinguish them,” Fanelli said. “Do we call them all planets and have 20 or 30 planets?”

The discovery does not require an immediate textbook revision, both instructors said.

Fanelli said the physics and astronomy department receive a new textbook edition every three years and use an online supplement to gather the most recent information.