The priceless facial expression and body movement accompanied by an innocent retail shopper before they exit a store with their paid merchandise, only to be rudely and obnoxiously stopped by the store's alarm which probably only sounded because they had half paper clip in their back pants pocket. Also known as the O-Shit Face.

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.