July 20, 1973
Robert Smithson dies in a plane crash, while surveying sites for his work Amarillo Ramp in the vicinity of Amarillo, Texas.
He is known as an earthworks artist, who also uses photography and film to document his environmental installations.
Spiral Jetty is his best-known work, visible depending on the level of the Great Salt Lake. It was submerged for about 30 years, but has been visible off-and-on in recent years, depending on drought conditions.