Ralph Bohlin

Ralph Bohlin

I have been thinking about absolute flux calibrations for over 50 years, since I was assigned to read a paper in Vol. 1 of JSQRT as an undergrad in 1965; and one of my tasks in grad school in 1967 was to calibrate a spectrometer for absolute flux measurements. From 1970 to 1982 I did absolute flux calibrations of several rocket experiments, including one to measure the absolute UV flux of Vega in 1972. I was in charge of absolute flux calibration of IUE (1979-1982) and the UIT payload on the Spacelab programs Astro 1 and 2. I have been Calibration Scientist at the STScI since 1982. The HST instruments for which I have done calibrations include FOS, STIS, NICMOS, ACS, and WFC3.

Awards and Memberships:

Phi Beta Kappa, Woodrow Wilson Graduate Fellowship, NSF Fellow, Princeton National Fellow, NRC Postdoctoral Award, Sigma Xi, American Astronomical Society, International Astronomical Union, 1999 STScI Individual Achievement Award 2016 STScI Individual Service Award for Lifetime CALSPEC Work


PhD - 1970, Princeton University, Astrophysics
BA - 1966, University of Iowa, Honors in Math and Physics


Science Interests:

  • Ultraviolet astronomy and instrumentation for rockets and satellites
  • Instrumental calibration and absolute stellar flux standards
  • Interstellar gas and dust.


Research Topics: Instrumentation; Absolute Flux Calibration


ORCID ID: 0000-0001-9806-0551


To contact one of our research staff members
please call 410-338-4700 or view the index for their email alias