A sexual act practiced by entire engineering classes. Engineering fields historically have had more males than females, as a way to engage in sexual acts where females are distributed evenly among males the whohr's circle was invented. All the girls in the class sit in a circle facing outwards while all the guys stand in a circle facing inward, surrounding the girls circle. Essentially a bukkake but with an emphasis on even distribution.

The safeguarding of Earth and other worlds from biological cross-contamination (i.e. billionaires with too much time on their hands).

Also known as “planetary protection.” Planetary protection / quarantine “reflects both the unknown nature of the space environment and the desire of the scientific community to preserve the pristine nature of celestial bodies until they can be studied in detail.”

There are two types of interplanetary contamination. Forward contamination is the transfer of viable organisms from Earth to another celestial body. Back contamination is the transfer of extraterrestrial organisms, if such exist, back to the Earth's biosphere.