A Once-in-11,000-Year Rendezvous
In 2076, the dwarf planet Sedna will make its closest swing by the Sun – an event that won’t repeat for another 11,400 years. This distant world, roughly three-quarters the size of Pluto, orbits so far out that it takes over 11 millennia to complete one circuit around the Sun. At its perihelion in the 2070s, Sedna will still be about 76 astronomical units out (around 7 billion miles, or nearly 11 billion km from the Sun) – almost three times farther than Neptune. After this brief visit to the inner fringe of the Oort Cloud, Sedna will retreat into darkness,
