Rachel Osten

Head, Instruments Division
Rachel Osten headshot

Dr. Rachel Osten is the head of the institute’s instruments division, where she leads a team of more than 160 scientific and technical staff that works to achieve the best possible science from the instruments onboard the Hubble Space Telescope, those planned for use aboard the James Webb Space Telescope, and ensures the continuation of excellence in science operations and user support for the upcoming Nancy Grace Roman Space Telescope. From 2016 to 2021, she served as the deputy mission head for the Hubble mission office, where she oversaw and promoted Hubble’s science operations to the astronomy community and the public. Prior to this, she was a mission scientist within the Hubble mission office from 2015 to 2016, and held the role of Webb deputy project scientist from 2013 to 2015. She is also a research scientist at Johns Hopkins University, where she’s held positions since 2011, and a full astronomer with tenure at the institute.

Dr. Osten joined STScI as an instrument scientist for Hubble’s Cosmic Origins Spectrograph (COS) and Space Telescope Imaging Spectrograph (STIS) instrument teams in 2008. She oversaw the first lifetime move of COS, and was instrumental in setting up and overseeing the initial time-dependent sensitivity monitoring for the spectrographs on COS after it was installed on Hubble. Prior to joining the institute, she was a Jansky Fellow at the National Radio Astronomy Observatory in Charlottesville, Virginia, and then a Hubble Fellow who worked both at the University of Maryland, College Park and NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

Dr. Osten studies the dynamics of the outer atmospheres of nearby stars with the goal of learning more about the processes occurring on them, how they connect to similar events seen on the Sun, and what the implications are for the stellar impact on the environments of extrasolar planets. She uses a nearly panchromatic approach, harnessing arrays of ground-based radio and optical telescopes as well as space-based ultraviolet, and soft and hard X-ray telescopes to perform these observations. She is a prolific and engaging speaker, having given more than 120 scientific presentations at professional conferences and to public audiences. Dr. Osten has authored or co-authored more than 50 peer-reviewed publications.

She served as the executive officer of the Decadal Survey on Astronomy and Astrophysics 2020 (Astro2020) and as a member of the 20-person Astro2020 steering committee. The committee developed a comprehensive research strategy for a decade of transformative science in space and on the ground. Before that, Dr. Osten was a member of the science and technology definition team for the Lynx large mission concept, one of four under consideration during Astro2020. She is also a member of the National Radio Astronomy Observatory’s science advisory council for the next generation Very Large Array, a concept for a large ground-based successor to the Jansky Very Large Array and Atacama Large Millimeter Array. Dr. Osten is a full member of the American Astronomical Society and International Astronomical Union, and has served on numerous advisory and review committees related to radio astronomy, high-energy astrophysics, and cool stellar science.


PhD in Astronomy, University of Colorado Boulder
MS in Astronomy, University of Colorado Boulder
AB in Physics and Astronomy, Harvard University


Science Interests:

  • Dynamics of cool star atmospheres
  • Multi-wavelength observations of stellar flares
  • Magnetic activity at radio and X-ray wavelengths, from stellar to sub-stellar regimes
  • Spectroscopy of stellar chromospheres and coronae


Research Topics: Stellar Astrophysics, Time Domain


Professional Websites:

Professional Website


ORCID ID: 0000-0001-5643-8421