Maarten Schmidt was a Dutch-born American astronomer who measured the distances of quasars. Born in Groningen, The Netherlands, Schmidt studied with Jan Hendrik Oort. He earned his Ph.D. degree from Leiden Observatory in 1956. He was a co-recipient, with Donald Lynden-Bell, of the inaugural Kavli Prize for Astrophysics in 2008. In 1959, he emigrated to the United States and went to work at the California Institute of Technology. In the beginning, he worked on theories about the mass distribution and dynamics of galaxies. Of particular note from this period was his formulation of what has become known as the Schmidt law, which relates the density of interstellar gas to the rate of star formation occurring in that gas. He later began a study of the light spectra of radio sources. In 1963, using the 200-inch reflector telescope at the Palomar Observatory, Schmidt identified the visible object corresponding to one of these radio sources, known as 3C 273 and also studied its spectrum.