Bid to solve dispute over planets http://news.bbc.co.uk/2/hi/science/nature/4273424.stm ‘10th’ Planet has moon companion http://news.bbc.co.uk/2/hi/science/nature/4304048.stm Information on the telescope used to discover Xena and Gabrielle http://www.astro.caltech.edu/palomarnew/sot.html Discovery of Xena’s moon http://www.gps.caltech.edu/~mbrown/planetlila/moon/index.html Discovery of 2003 UB313 the 10th Planet http://www.gps.caltech.edu/~mbrown/planetlila/ International Astronomical Union http://www.iau.org Kuiper Belt page http://www.ifa.hawaii.edu/faculty/jewitt/kb.html The newly discovered “planet” 2003 UB313, otherwise known as Xena, now has a companion in the solar system. Originally spotted in 2003, Xena was not officially announced until July of 2005. On the heels of the publication of Xena’s existence, comes the revelation that Xena has a moon, named Gabrielle. The names Xena and Gabrielle are only temporary, used by some astronomers because they are simpler to remember than names such as 2003 UB313. To decide the official name, the International Astronomical Union (IAU) must first decide if Xena is in fact a planet, then they will decide if the discoverers’ proposed name will be used. The astronomers who discovered both Xena and Gabrielle cannot reveal their proposed name, so until then the nicknames will have to suffice. Xena was found in the Kuiper Belt, which is a huge region of icy planetary bodies that orbit beyond Neptune in the distant region of the solar system. The discovery of this new planet and its moon has reignited the debate about what properties an object must possess in order to be classed as a planet. Prior to this newest discovery, Pluto’s status as a planet was already in question by some astronomers. But while Pluto rests on 100 years of history as a planet, newly discovered bodies are not so easily defined. Until the IAU can agree on a definition of a planet, Pluto will continue to hang on tenuously to its status as one of nine planets, and its mnemonic device, My Very Excellent Mother Just Sent Us Nine Pizzas, will remain as well. While the public awaits the final definition of what constitutes a planet, both school children and adults alike can rest easy and will not yet have to ponder what else our excellent mother will send us. The first link takes users to the announcement of the discovery of Xena in August made in the Yale Daily News. The second link takes the user to an article from the BBC further discussing the planetary debate. The third link is a BBC article that includes this week’s announcement about Xena’s moon. For further knowledge about the astronomers and telescope involved with these two discoveries, among others, the fourth link will take the user to their website. The fifth and sixth link will take the user directly to the discovering astronomers’ website for the announcements about the new moon, Xena, and information on the progress of the IAU. If you are interested in the IAU, the seventh link will take you to their website. And finally the last link will take you to a website dedicated to providing more information on the Kuiper Belt and the icy bodies that make up this far region of our solar system.