What is the largest known orbit of an object around the sun? I searched on yahoo, but nothing.
do a search for HIDALGO its record may have been beaten by
new observations .
Sedna, 2000 CR105, 2000 OO67, and "many comets" - according to Jewitt (click on "Sedna" on the left). If you like lists, the MPC has a nice one of Centaurs and Scattered Disk Objects (look in the column marked "Q" for the ones that go furthest from the Sun).
AFAIK, there is no single, reliable list of comets (past and present) and their last known orbits. There are plenty of comet lists, and you can get lots of ephemerides ... happy searching!
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