The discovery of Varuna was formally announced in a Minor Planet Electronic Circular on 1 December 2000. It was given the provisional designation , indicating that it was discovered during the second half of November 2000. Varuna was the 2667th object observed in the latter half of November, as indicated by the last letter and numbers in its provisional designation. At the time, Varuna was thought to be one of the largest and brightest minor planets in the Solar System due to its relatively high apparent magnitude of 20 for a distant object, which implied that it might be around one-fourth the size of Pluto and comparable in size to the dwarf planet .