Joseph Kosuth, Self-Defined Object (Green), 1966. Green neon mounted directly on the wall 10 x 172.5 cm. On view at Sprüeth Magers, Berlin through August 31

James Turrell, Prado, Red, 1968. On view at Almine Rech, Paris through July 13

Fabien Giraud & Raphael Siboni, Sans Titre (la vallée Von Uexkull), 2009. On view at the Museum of Old and New Art in Tasmania through July 28

Robert Irwin, Picadilly. Forty-seven fluorescent tubes. On view at Pace, London through August 17