90377 Sedna is a trans-Neptunian object: one of the two most distant large objects yet found orbiting the Sun (the other being 2012 VP-113). Its precise classification remains uncertain. The Minor Planet Center currently classifies it as a Scattered Disk Object, while others place it at the inner margin of the Oort Cloud. Sedna, named after the Inuit goddess of the ocean, is currently three times further away than Pluto, the average distance of which from the Sun is 5.9 billion km (3.6 billion miles). At its most distant, Sedna is almost 150 billion km (93 billion miles) from the Sun, or 990 times Earth's solar distance. It has an orbital period, or year, of some 10,500 years. Its surface temperature is believed to be about -240°C (-400°F).

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