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发帖数: 667 | 1 Astronomers have discovered another TNO last year, but this time the
one they found is quite large: 1100 miles across, almost 3/4 the size of
Pluto.
It is tentatively named Sedna, the Innuit Goddess of Sea.
Sedna is currantly about 90AU away from the Sun, and in its perihelion
it might move as close as 72AU to the Sun. Its orbit, however is quite
elliptic. It is believed its aphelion can be as far as 1000AU.
Sedna is too small to be a planet. It's not a KBO, either, for it's too
far away. It cou |
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