Greenstein did important work in determining the abundances of the elements in stars, and was, with Maarten Schmidt, the first to recognize quasars as compact, very distant sources as bright as a galaxy.
While its star-like appearance suggested it was relatively nearby, the spectrum of 3C 273 proved to have what was at the time a high redshift of 0.158, showing that it lay far beyond the Milky Way, and thus possessed an extraordinarily high luminosity.
Helmut Schmidt | Eric Schmidt | Helle Thorning-Schmidt | Sint Maarten | Harold von Schmidt | Hans Schmidt | Otto Schmidt | Mike Schmidt | Maarten van Heemskerck | Schmidt camera | Karl Schmidt-Rottluff | Johann Friedrich Julius Schmidt | Jean Schmidt | HNLMS Maarten Harpertszoon Tromp | Wolfgang Schmidt | Stanley F. Schmidt | Schmidt-Cassegrain telescope | Schmidt | Miloslav Schmidt | Maarten Tromp | John Schmidt | Hans Schmidt (wrestler) | Werner Schmidt | Steve Schmidt | Nicolaus Schmidt | Mary Schmidt Campbell | Maarten Swings | Maarten Schmidt | Maarten Gerritsz Vries | Maarten Baas |
The first Kavli Prize for astrophysics was awarded to Maarten Schmidt and Donald Lynden-Bell.