Tenth planet is second most bright object in solar system

Xena, which is unofficially called the tenth planet, is the second most shiny known object in our solar system.

Scientists are scrambling to explain where Xena got its sparkle. Some suggest that it might have enough heat to belch methane, despite being in the coldest region of the solar system.

The new notion of Xena arises from Hubble Space Telescope images that were released this week. The images reveal that Xena, the most distant known object in our solar system, isn't quite the big shot that scientists had thought it was.

More info over at Science News.