Sjur Refsdal

Sjur Refsdal ( born December 30, 1935 in Oslo, † January 29, 2009 ) was a Norwegian astrophysicist.

Life

Refsdal studied at the University of Oslo and was there in 1970 at the Institute for Theoretical Astrophysics for dr. phil (os) doctorate (equivalent to the German Habilitation rather ). From 1970 to 2001 he was professor at the Hamburg Observatory of the University of Hamburg and lived until his death on 29 January 2009 as Professor Emeritus in Oslo. He was a member of the Norwegian Academy of Sciences.

Work

Refsdals main interest since 1963 gravitational lensing, although he also published some important work on stellar evolution. He realized in 1963 that the newly discovered quasars cosmic light sources were available, the gravitational lensing observable and made ​​usable as a tool of astrophysics with galaxies as lenses. He predicted that the masses of galaxies and the age of the universe or the Hubble constant can be determined by this effect. With his doctoral student Kyongae Chang, he developed the concept of gravitational microlensing effect. Since 1979, with the so-called Doppelquasar the first gravitational lens effect was observed, the theory and observation of this effect has become an important branch and standard tools of astrophysics.

Awards

Refsdal 1994 received an honorary doctorate from the University of Liege in Belgium.

On 1 February 2005, he received the Medal of Merit of the Norwegian king in gold.