space fireflies Fz^
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The phenomenon whereby human waste ejected out into space is hit by sunlight or another light source, causing it to glitter and resemble a group of fireflies. Astronaut John Glenn of Project Mercury famously reported this phenomenon after his first trip into space; they are seldom seen anymore, however, due to the strict legislation that has been enacted to prevent the ejecting of waste and garbage into space, such as the Outer Space Waste Regulations and Outer Space Environment Standards Law.