display | more...
Provisional name for the newly-discovered tenth planet of our solar system, currently given the designation 2003 UB313.

On July 30, 2005, it was offically announced that astronomers at the California Institute of Technology (ie. CalTech) discovered the planet, which is twice the size of Pluto, which until now had been the furthest planet from the sun in our solar system. Xena's size helped in deciding the object was a true planet and not an asteroid (sometimes called a minor planet); this is not the case with the previously-discovered Sedna, which is generally agreed to be too small to be a true planet.

Xena was discovered in the Kuiper Belt after a five year search by the CalTech team headed by Dr. Michael Brown. It was photographed on October 21st, 2003 by Brown, Chad Trujillo of the Gemini Observatory and David Rabinowitz of Yale University1 using a 48-inch telescope at the Palomar Observatory. However, Xena moves so slowly that movement wasn't detected until this past January.

With a powerful telescope, you should be able to see Xena in the constellation Cetus, with best results between now and the next six months.

The Facts:

  • Size: 1,700 miles in diameter.

  • Distance from the Sun: around 9 billion miles.

  • Orbit:
    • Orbital Period: 203,500 days (560 years)
    • Aphelion: 97.610 AU
    • Perihelion: 37.808 AU
    • Inclination of Angle: 44.177° to the ecliptic.

  • Apparent magnitude: 19

  • Temperature: -240° C.

  • Make-up: unknown, but presumed to be similar to Pluto, as methane ice has been detected on its surface.

  • Albedo: 0.5–1.0

  • Color: Looks pretty whitish.

1. This is the same team that discovered Sedna on November 14, 2003.

Log in or register to write something here or to contact authors.