A form of radiation that is normally fatal to humans, scrambles transporters and phasers, and saturates the planet Tau Cygni V where a lost colony nevertheless survived.
Hyperonic radiation shapes the episode The Ensigns of Command. The Sheliak demand the removal of humans from Tau Cygni V, a planet where the Federation believed no human could live. The colony ship Artemis had landed there ninety years before, and after heavy early losses the settlers' descendants adapted.
The radiation makes it impossible to use the transporter, so evacuating more than fifteen thousand people would take weeks the Sheliak will not grant. It also rules out sending anyone but Data, who is immune.
Data arrives by shuttle to persuade a proud community to leave. His phaser will not work in the radiation until he modifies it, and he uses the rebuilt weapon to wreck the colony's aqueduct and show what the Sheliak could do.