William Herschel

Herschel changed his name after moving to England. His sister Caroline Herschel worked with him for many years and also did several discoveries on her own. His son John Herschel also became a famous astronomer.

William Herschel and Infrared Radiation

Herschel discovered infrared radiation by passing sunlight through a prism and holding a thermometer just beyond the red end of the visible spectrum. The thermometer indicated a temperature increase and this led to Herschel's conclusion that there must be an invisible form of energy.

Links:

• William Herschel's Deepsky Catalog (http://www.seds.org/messier/xtra/similar/herschel)