Comet Shit
The comet shit can be defined as a large hard turd (sometimes nearly perfectly round like that of a donut hole) followed by a spray of loose diarrhea. When defecating, often times the thrust necessary to push this initial round turd "out" creates a rocketing ball of feces followed by a shower of watery slime.
Dude, my guts are bubbling. I feel a Comet Shit coming on..
Shit Comet
An unconscious human who has shat him or herself during free fall at terminal velocity.
Joey thought it would be funny to take Benadryl and laxatives at the same time just before sky diving. Little did he know, this would affect his ability to pull his chute, therefore causing him to become a Shit Comet.