5380 Sprigg, provisional designation 1991 JT, is a background asteroid from the middle regions of the asteroid belt, approximately 7 kilometers (4.3 miles) in diameter. It was discovered on 7 May 1991, by Australian astronomer Robert McNaught at Siding Spring Observatory in New South Wales, Australia.[8] It was named after Australian geologist Reg Sprigg.[2]
This minor planet was named after Reg Sprigg (1919–1994), Australian exploration geologist, oceanographer, biologist, author and conservationist. In 1946, he discovered the pre-Cambrian Ediacara biota, an assemblage of some of the most ancient animal fossils known. He is also the founder of the Arkaroola Wilderness Sanctuary which also hosts a small observatory. The naming was proposed by astronomer Duncan Steel.[2] Naming citation was prepared by the Sprigg family and published on 11 April 1998 (M.P.C. 31609).[9]
A rotational lightcurve of Sprigg was obtained from photometric observations by astronomer Maurice Clark at Texas Tech University in October 2013. Lightcurve analysis gave a rotation period of 3.219 hours with a brightness amplitude of 0.68 magnitude, indicating that the body has a non-spheroidal shape (U=3-).[6]
Diameter and albedo
According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Sprigg measures 6.606 kilometers in diameter and its surface has an albedo of 0.280,[4][5] while the Collaborative Asteroid Lightcurve Link assumes a standard albedo for carbonaceous asteroids of 0.057 and calculates a larger diameter of 12.75 kilometers with an absolute magnitude of 13.2.[3]