2003 EL61 Precovery!

In the world of exploration and discovery, the practice of mounting expeditions to faraway locales is an established tradition. That same tradition applies also in the realm of astronomy, where most assets are directed at distant regions. Witness images such as this, titled Hubble Reveals the Heart of the Whirlpool Galaxy: (Image Credit: NASA and The Hubble Heritage Team (STScI/AURA)) Astronomers recently announced the discovery of a planet orbiting the star Gliese 876, closer to home, but still about 15 light-years distant. (Credit and Copyright: Digitized Sky Survey ) Explorers and adventurers frequently overlook exciting discoveries in their own back yards. Astronomers do also, with eyes and instruments focused on distant regions. But not always... [...] Jose-Luis Ortiz, an astronomer at the Sierra Nevada Observatory in Spain, and colleagues discovered the object when they re-analysed observations they had made in 2003. Then, they scoured older archives and found the object in images dating back to 1955. Based on these so-called "precoveries", they calculated the object's orbit and sent urgent emails asking people around the globe to observe the new find. Amateur observers Salvador Sanchez, Reiner Stoss, and Jaime Nomen found it on Thursday using a 30-centimetre telescope in Mallorca, Spain. "I am not going to sleep tonight," said Stoss, a mechanical engineering student in Darmstadt, Germany. "To find an object bigger than Pluto - it's like the X Prize," he said, referring to the $10 million prize for private spaceflight won in 2004. The observations were then verified by the International Astronomical Union's Minor Planet Center (MPC) in Cambridge, Massachusetts, US, which designated the object 2003 EL61. [...] (Image credit: Consejo Superior de Investigaciones Científicas Instituto de Astrofísica de Andalucía) This follows the discovery of other bodies in the same region. [...] On 15 March 2004, astronomers from Caltech, Gemini Observatory, and Yale University announced the discovery of the coldest, most distant object known to orbit the sun. The object was found at a distance 90 times greater than that from the sun to the earth -- about 3 times further than Pluto, the most distant known planet. [...] This discovery has been named Sedena. Prior to that was the precovery of Quaoar. There is still much debate as to what exactly constitutes a planet (as an exercise, enter define: planet in a Google search and scan the definitions), and the status of these three has not been determined. Tagged as Science, Space, Sun, Star, Solar System, Planet, Earth, Pluto, Astronomy, Sedna, Quaoar, 2003 EL61, Kuiper belt, Whirlpool Galaxy, Gliese 876