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David Helfand


David Helfand is a professor of astronomy at Columbia University and serves as chair of the Astronomy Department. His work has covered many areas of modern astrophysics including radio, optical, and X-ray observations of sources from stars to quasars. Currently, he is involved in a survey of the Milky Way Galaxy using the Very Large Array radio telescope. Dr. Helfand will be featured in National Geographic’s “Known Universe: Cosmic Collisions” television series, starting April 1, 2010.

Interviews with David Helfand
David Helfand on risk from killer asteroids