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 Exoplanet Discovery and Science: People
Robert  Zellem's Picture
Jet Propulsion Laboratory
M/S 169-237
4800 Oak Grove Drive
Pasadena, CA 91109

Robert Zellem

Rob is a scientist at NASA’s Jet Propulsion Laboratory working on ground- and space-based observations of the atmospheres of exoplanets, planets outside of our Solar System. Specifically, Rob has been commissioning NESSI, a new multi-object spectrograph at Palomar Observatory that will study tens of these alien worlds, has been involved in benchmarking the performance through simulations of NASA and ESA exoplanet-dedicated missions, and leading citizen science projects to help aid in the characterization of exoplanets.

Rob was born just outside the Philadelphia city limits but grew up in Hendersonville, TN. He went to Villanova University where he graduated with his Bachelor of Science in Astronomy and Astrophysics, minoring in Physics, Mathematics, and Classics, and getting an Honors Concentration. HIs love of travel and learning about other cultures brought him to University College London in England where he got his MSc in Space Science. He then moved out west to Tucson, AZ, where he received his PhD in Planetary Sciences from the Lunar and Planetary Laboratory at the University of Arizona. He is currently a scientist at NASA’s Jet Propulsion Laboratory. When he's not observing exoplanets, he enjoys jazz piano, cooking, trying not to kill all his plants, brewing beer, playing ice hockey, and fantasizing about retiring to work at Disney.

  • PhD in Planetary Science – Lunar & Planetary Laboratory – University of Arizona
  • MSc with Distinction in Space Science – University College London
  • BS in Astronomy & Astrophysics – Villanova University

Research Interests

Spectroscopy of transiting exoplanets to measure their atmospheric molecular abundances and thermal structure


Nancy Grace Roman Space Telescope Icon Nancy Grace Roman Space Telescope
The Roman Space Telescope is a NASA observatory designed to unravel the secrets of dark energy and dark matter, search for and image exoplanets, and explore many topics in infrared astrophysics.

Selected Publications
  1. Zellem, Robert; et al. (2015) XO-2b: A Hot Jupiter with a Variable Host Star That Potentially Affects Its Measured Transit Depth, ApJ, 810, 11.
  2. Zellem, Robert; et al. (2014) The ground-based H, K, and L-band absolute emission spectra of HD 209458b, ApJ, 796, 48.
  3. Zellem, Robert; et al. (2014) The Spitzer/IRAC 4.5 micron full-orbit phase curve of the hot Jupiter HD 209458b, ApJ, 790, 53.

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