International Ultraviolet Explorer was considered the most successful astronomical satellite ever. The human eye can perceive light with wavelengths between roughly 350 (violet) and 700 (red) nanometres. Ultraviolet light has wavelengths between roughly 10 nm and 350 nm. UV light can be harmful to human beings, and is strongly absorbed by the ozone layer. This makes it impossible to observe UV emission from astronomical objects from the ground. Many types of object emit copious quantities of UV radiation, though: the hottest and most massive stars in the universe can have surface temperatures high enough that the vast majority of their light is emitted
The Sun Is Often Out The Sun Is Often Out The Sun Is Often Out (stylized as THE SUN iS OfTEN oUT) is the debut album by Longpigs, released in 1996 on U2's record label, Mother Records. Five singles were released from the album, initially to little success. The first two - "She Said" and "Jesus Christ" - both failed to crack the UK Top 40, both stalling at No. 67. The third single - "Far" fared a little better, scraping into the Top 40, reaching No. 37 and received significant radio airplay, particularly on the national pop and rock radio station, BBC Radio 1.