Summer Student Snaps New Planet

Working at the Armagh Observatory with Dr Simon Jeffery and Dr Tolis Christou, Nuffield Science Bursary scholar Elizabeth Connolly was using an internet connection to control the Faulkes Telescope in Hawaii. During her half-hour observing session, she briefly turned the telescope to where the new planet had been discovered. After taking a photograph with the 2-metre telescope, she compared the new image with an old image of the same patch of sky. The new planet was clearly visible as a faint smudge amongst other background stars, where before there had been nothing. Asked what she felt about sighting the new planet, Elizabeth, a student at Loreto Grammar School, Omagh, said, “Wow, its cool! Its amazing how a little tiny dot can make you realise your complete insignificance in the universe!”

2003 UB313 was discovered by a team of Californian astronomers on January 5, 2005 from images taken in 2003, and the discovery was announced on July 29, 2005. It has been described as “definitely bigger than Pluto”, and is the largest known member of a family of objects orbiting the Sun beyond Neptune. Right now, 2003 UB313 is three times further from the Sun than Neptune, and 97 times farther from the Sun than Earth. Since the discovery of Pluto in 1930, the solar system has contained nine planets. Being larger than Pluto, 2003 UB313 might now be considered as the tenth planet in the Solar System, and is already being described as such by NASA. However, the status of Pluto as a planet has been subject to debate for some time. Both Pluto and 2003 UB313 are considerably smaller than the Earth and quite unlike the giant outer planets Uranus and Neptune. Also, they travel in orbits that are quite unlike the other planets. So what is a planet? The International Astronomical Union, which adjudicates on all matters astronomical, has been reviewing the definition of the term. Whether Pluto remains a planet, and whether it will be joined by a new family of outer planets or whether these ghostly wanderers will be downgraded, is a question not just for astronomers, but for everyone. Meanwhile, 2003 UB313 awaits a real name rather than just a number.