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When two males spacedock with either a turdildo or fresh poop. The Cosmonauting occurs when the males insert the turdildo into each others anuses and have a sort of homosexual intercourse with it. Heterosexual cosmonauting is called Spacedocking.
Ryan and Steve were very excited to be Cosmonauting together, but their fun was ruined when Denise walked in and caught them with a turdildo up their asses.
by SampsonCatt December 13, 2007