History of the telescope of the IRAS satellite in 1983 revolutionized infrared astronomy from space. This reflecting telescope which had a mirror, operated for nine months until its supply of coolant (liquid helium) ran out. It surveyed the entire sky detecting 245,000 infrared sources—more than 100 times the number previously known. Although optical telescopes can image the near ultraviolet, the ozone layer in the stratosphere absorbs ultraviolet radiation shorter than 300 nm so most ultra-violet astronomy is conducted with satellites. Ultraviolet telescopes resemble optical telescopes, but conventional aluminium-coated mirrors cannot be used and alternative coatings such as magnesium fluoride or lithium fluoride are used
The Midnight Sun (C Duncan album) beauty." A mixed review by Billy Hamilton of "Under the Radar" found the tracks to only be "subtle variations of the same song," opining the album was mostly "lush and immersive" and little else. "The 405" Robert Whitfield criticized the LP's atmospheric elements for getting in the way of the lyrics and vocals: "C Duncan’s vocals are often buried under so many layers that what message or meaning he wishes to communicate is lost. Ultimately it means that The Midnight Sun is more of an atmospheric experience, than an emotive one." "The Midnight Sun" made it to the shortlist of