Marc Rafelski

Marc Rafelski headshot

Dr. Marc Rafelski is the Cosmic Origins Spectrograph (COS) branch manager for the Hubble Space Telescope (HST). Previously he worked with the Mikulski Archive for Space Telescopes (MAST) and the Wide Field Camera (WFC3) on HST. For WFC3 he worked on calibration improvements for the UVIS detector. For MAST he worked on initiatives to improve support for spectroscopic data.

Dr. Rafelski's research aims to further our understanding of the formation and evolution of galaxies by studying the physical characteristics and processes of high redshift galaxies and their associated gas reservoirs, inflows, and outflows. He has been working on this via chemical abundance and star formation studies of quasar absorption line systems, which provide a unique laboratory for understanding the conversion of cold gas into stars at high redshift. He also studies the galaxies directly in emission, learning about their star-formation and resolved structure from high-resolution ultraviolet imaging and their physical properties via low-resolution grism spectroscopy.

Dr. Rafelski has used a wide range of telescopes both from the ground and space covering the ultraviolet through infrared wavelengths, using over 15 instruments for imaging and spectroscopy on more than 6 telescopes. He is an active member of the research community and has published more than 70 peer-reviewed articles, which have appeared in the Astronomical Journal, the Astrophysical Journal, the Monthly Notices of the Royal Astronomical Society, and Astrophysics and Space Science Library journals. He regularly presents at conferences and meetings, including more than 50 around the world. Dr. Rafelski is also affiliated as an Associate Research Scientist at Johns Hopkins University.


PhD in Physics, University of California, San Diego
MS in Astronomy, University of California, Los Angeles
BS in Physics and Astronomy, University of Arizona


Science Interests:

  • Galaxy evolution
  • Galaxy chemical evolution
  • Absorption line systems
  • Galaxy gas accretion and outflows
  • Star formation
  • Intergalactic medium
  • Circumgalactic medium
  • Ultraviolet astronomy


Research Topics: Star Formation, Histories, and Evolution; High-Redshift Galaxies; Galaxy Formation and Evolution; Astrochemistry, Chemical Abundances; Intergalactic Medium (IGM); Circumgalactic Medium (CGM); gas in and around galaxies



Professional Website

The Panchromatic Hubble Ultra Deep Field: Ultraviolet Coverage

Galaxies and the Circumgalactic Medium (GCGM) Research Group


ORCID ID: 0000-0002-9946-4731


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