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Dwarf-planet Sedna is not alone
Solar System formation models indicate that the remote 1,000-km-diameter dwarf planet Sedna — 76 astronomical units (AU) from the Sun at its closest (perihelion) point — could be a link between the Kuiper belt objects orbiting at 30 to 50 AU and the as-yet unseen outer Oort cloud, some 10,000 AU from the Sun. Chadwick Trujillo and Scott Sheppard now report the presence of a second Sedna-like object, 2012 VP113, with a perihelion of 80 AU. This discovery confirms that Sedna is not an isolated object. Both bodies may be members of a population of inner Oort cloud objects that could outnumber all other dynamically stable populations in the Solar System.
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