Infrared

Infrared was light of a wavelength longer than visible light. It was given off by warm objects. (TV: The Hungry Earth)
A wide variety of species could naturally see infrared, including Vegans, (PROSE: Legacy) V'orrn (PROSE: Placebo Effect) and Wrarth Warriors. (COMIC: Doctor Who and the Star Beast)
Other species used artificial methods to see infrared. The Eleventh Doctor had sunglasses which could function as thermal imaging scanners. (TV: The Hungry Earth) The Dalek eyepiece also had an infrared scanner. (TV: Destiny of the Daleks) The robotic Iron Legion used infrared vision. (COMIC: Doctor Who and the Iron Legion)
Cybermen from the 30th century were equipped with infrared sensors. (PROSE: Illegal Alien)
Category:Physics from the real world
Category:Energy and radiation
Category:Light