Caption: New Zealander Roy Kerr (1934--) lectures at the 11th Marcel Grossmann Meeting (in honor of Marcel Grossmann (1878--1936)) in Berlin, 2006

Kerr is the discoverer (in 1963) of the Kerr solution for the Einstein field equations for the spacetime outside a rotating spherically-symmetric body. The Kerr solution predicts the existence of Kerr black holes.

In the image, Kerr is using an overhead projector, an obsolete kind of projector---you still see a few of them gathering dust in the odd corners of classrooms.

Apropos of nothing at all, Kerr shares his birthday with Maria Gaetana Agnesi (1718--1799), Kenji Mizoguchi (1898--1956), Henry Fonda (1905--1982), Margaret Sullavan (1909--1960), Liberace (1919--1987), Adrienne Rich (1929--2012), and Pierce Brosnan (1953--)---the things Wikipedia gives to idle minds.

Credit/Permission: © Martin Petrasek (AKA User: Martincz), 2006 / Creative Commons CC BY-SA 3.0.
Image link: Wikipedia: File:SmKIF 5234.JPG.
Local file: local link: roy_kerr.html.
File: Astronomer file: roy_kerr.html.