Independent Online Edition > Science & Technology : app6:
It is a tiny white dot even in the most powerful telescopes, but a dot that moves, albeit slowly, against the background of distant stars.
That means it must be a planet, so now object 2003UB313, spotted two years ago by astronomers in California, has been officially identified as the 10th planet in the solar system, and tentatively christened Xena.
The body is believed to be about 1,700 miles in diameter, about a quarter the size of the Earth, and about one-and-a-half times the size of Pluto, the ninth and last planet to be discovered, in 1930.
But at nearly 10 billion miles out, Xena is the most distant object detected orbiting the Sun, three times as far out as Pluto and 97 times as far out as the Earth. Its full orbit takes 560 years.
This is cool, but I don't know that they had to name it after the Warrior Princess.