Today we quite rightly remember O.J. Eggen for the pioneering paper on kinematics and formation of the Milky Way galaxy (Eggen, Lynden-Bell, and Sandage 1962) and for work with Jesse Greenstein (1964-67) identifying the first large, uniform sample of white dwarfs. But his astronomical career had less happy aspects. The first of these was work between 1948 and 1956 on CMDs for nearby clusters and the solar neighborhood, using the ``International" and (P,V) two-color systems. He described no fewethan five separate, sharp main sequences (``trend lines") in the resulting data and (in the words of Whitford) lost a battle with [Harold] Johnson," whose three-color, UBV, work with W.W. Morgan did not find such substructure in the main sequence but did reveal that a separate UV band, cleanly on the other side of the Balmer discontinuity from the blue band, was essential for stellar work. The resulting unpleasantness led to Eggen's departure from Lick Observatory. The reality and implications of his later moving groups and their connection to trend lines will also be explored.
American Astronomical Society Meeting Abstracts
- Pub Date:
- December 2000