Schwassmann-Wachmann 1

Schwassmann-Wachmann 1

(shvahss -mahn vahk -mahn) A comet that moves in a near-circular orbit between the orbits of Jupiter and Saturn and suffers from random outbursts: increases in brightness by up to seven magnitudes that last for a few weeks. A considerable number of comets suffer outbursts and many theories have been put forward to explain them. These include pressure release from gas pockets of methane and carbon dioxide, explosive chemical reactions involving free radicals (CH, OH, and NH), temperature-induced phase changes in amorphous ice, impact cratering by interplanetary boulders, and spin- and age-induced nuclear break-up. Impact and break-up are the most likely causes.