The mission of the Exoplanet Exploration Program is threefold – to search for planets beyond our solar system, characterize them, and look for life among the stars. The scientists and engineers who work at NASA's exoplanet program work daily to make those goals a reality.


  • Gary Blackwood
    Gary Blackwood
    Program Manager
    Dr. Gary H. Blackwood is the Program Manager for the NASA Exoplanet Exploration Program at the Jet Propulsion Laboratory. He earned his B.S., M.S. and Ph.D. in Aeronautical and Astronautical Engineering from MIT. He has been an employee at JPL since 1988 and has worked on technology development for precision astronomical instruments and astrophysics missions, including the Hubble Wide/Field Planetary Camera-2, the StarLight formation-flying interferometer, the Space Interferometry Mission and the Terrestrial Pla... more
  • Karl Stapelfeldt
    Karl Stapelfeldt
    Program Chief Scientist
    Dr. Karl Stapelfeldt is the Chief Scientist for NASA’s Exoplanet Exploration Program at the Jet Propulsion Laboratory. His research is focused on circumstellar disks, planet formation, exoplanets, and the design of future missions and instruments that could achieve major scientific advances in these areas. Dr. Stapelfeldt began his NASA career as a post-doctoral research fellow at JPL in 1993. As a JPL scientist from 1994 to 2011, he worked on the Hubble Space Telescope WFPC2 instrument, Spitzer Sp... more
  • Eric Mamjek
    Eric Mamajek
    Deputy Program Chief Scientist
    Dr. Eric E. Mamajek earned his B.S. in astronomy and astrophysics at Penn State, an M.Sc. in physics from the University of New South Wales/ADFA, and his M.S. and Ph.D. in astronomy from the University of Arizona. He was previously a Clay Postdoctoral Fellow at the Harvard-Smithsonian Center for Astrophysics, Associate Astronomer for the National Optical Astronomy Observatory at Cerro Tololo Inter-American Observatory in Chile, and Professor of Physics & Astronomy at University of Rochester, w... more
  • Anjali Tripathi
    Anjali Tripathi
    Science Ambassador
    Dr. Anjali Tripathi is an astrophysicist and the Science Ambassador for NASA’s Exoplanet Exploration Program. As the program’s lead science communicator, she works to make science accessible for all. Her research has explored how exoplanets form and lose their atmospheres. Connecting science to society, she previously led science and climate policy at the White House. She earned her Ph.D. and Master of Arts in astrophysics from Harvard, Master of Philosophy in astronomy from the University of Cambridge as a Marshall Scholar, and Bachelor of Science degree in physics from MIT.
  • Nick Siegler
    Nick Siegler
    Program Chief Technologist, Technology Development Manager
    Dr. Nick Siegler is an astrophysicist and the Chief Technologist for NASA's Exoplanet Exploration Program located at the Jet Propulsion Laboratory. With collaborators from all over the country he helps identify and mature technologies needed to enable possible future NASA missions that will ultimately look for evidence of life on exoplanets. He has worked in a variety of systems engineering and project management roles for the last nine years. Prior to JPL, Dr. Sieg... more
  • Keith Warfield
    Keith Warfield
    Program Chief Engineer
    Keith Warfield is the Chief Engineer for the NASA Exoplanet Exploration Program (ExEP) and the Habitable Exoplanet Imaging Mission (HabEx) Study Office Manager. HabEx is one of four large mission studies funded by NASA as preparation for the coming 2020 Astrophysics Decadal Survey. Prior to his present roles, Mr. Warfield was the Study Office Manager overseeing the designs and concept development for two sub-billion dollar exoplanet direct-imaging mission studies (Exo-C an Exo-S). From 2006 to 2013, Mr. W... more
  • Anya Biferno
    Anya Biferno

    Exoplanet Communications Manager
    Anya Biferno is the Public Engagement Manager for NASA’s Exoplanet Exploration Program, coordinating communications activities across the theme of exoplanet science, missions, and technology development. She has been with ExEP since 2008. In addition to her communications role with ExEP, Ms. Biferno is the JPL Co-I on the Universe of Learning education cooperative agreement (PI-STScI). She has a BA in Global Politics from the California State University, Los Angeles and a Masters in Public Administration from the University of Southern California.

  • Chas Beichman
    Charles Beichman
    NExScI Executive Director
    Dr. Beichman has been a leader in infrared astronomy and exoplanet research for over 30 years. His primary scientific interests include the formation of solar type stars and debris disks around both young and mature stars (IRAS, Spitzer, Keck Interferometer, JWST), the detection and characterization of planets around young and mature stars (Palomar, SIM, Spitzer, JWST), and the study of brown dwarfs (2MASS, Keck, WISE, Spitzer, HST, JWST). He has been a member of science teams on a variety of sky surve... more
  • Sean Carey
    Sean Carey
    NExScI Manager
    Dr. Sean Carey earned his PhD in Physics from Rensselaer Polytechnic Institute in 1995. He is currently manager of the Spitzer Science Center and task lead for the NEOCam Science Data Center at Caltech/IPAC. Previously he was a Senior Astronomer at Boston College and Geophysics Scholar and National Research Council Postdoctoral Fellow at the Air Force Research Laboratory. He is an expert in the calibration of infrared telescopes and has received a NASA Exceptional... more
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    Case Bradford
    S5 Activity Manager
    Dr. Samuel “Case” Bradford has been an employee at NASA’s Jet Propulsion Laboratory since 2006. He is the S5 Starshade Technology Development activity manager. At JPL Case has been a consistent champion for technology development and flight infusion, supporting missions from pre-Phase-A to operations, including support for Starshade mechanical activities since 2009. From 2014 to 2022 he served as the supervisor of the Advanced Deployable Structures group where he managed a wide portfolio of... more
  • David Ardila
    David Ardila
    NN-Explore Project Manager
    Dr. David Ardila is an expert in star and planet formation, with over 200 publications on this and other areas. He is an expert in spectrometer design, high contrast imaging, and general instrument architecture, both for Astrophysics and Earth Science missions. He has worked in the formulation of new missions for NASA, in roles including instrument scientist, capture lead, and system engineer. He was mission manager for NASA’s K2 mission, NASA-ESA liaison for the Herschel Space Telescope, and Ca... more
  • Brendan Crill
    Brendan Crill
    Deputy Program Chief Technologist, Deputy Technology Manager
    Dr. Brendan P. Crill has worked at NASA’s Jet Propulsion Laboratory since 2008 and joined the Exoplanet Exploration Program in 2016 as the Program’s Deputy Technology Development Manager. His science career began in cosmology, with an undergraduate degree from Brown University and a Ph.D. in physics from Caltech. He worked on developing instrumentation for measurements of the Cosmic Microwave Background (CMB). His work on the receiver of the BOOMERANG ball... more
  • Mary Romejko
    Mary Romejko
    Program Business Manager
    Mary Romejko has been an employee of NASA's Jet Propulsion Laboratory since 1983. She has held positions with increasing levels of responsibility in Financial Controls and is currently the Program Business Manager Exoplanet Exploration Program Office. Ms. Romejko receives programmatic direction from the Exoplanet Exploration Program Office. In this capacity she is the primary business interface with other business organizations, both internally and externally. She leads the implementation and perfor... more
  • Ray Lemus
    Ray Lemus
    Program Business Administration Manager
    Ray Lemus earned a B.S. in Chemical Engineering from the New Jersey Institute of Technology and an MBA from the Anderson School of Management at UCLA. He has been an employee at NASA’s Jet Propulsion Laboratory since 1996. Early in his career, Mr. Lemus worked as a process engineer in Chevron’s largest refinery in the San Francisco Bay area, responsible for the technical performance of various fuel-oil plants. Subsequent to his MBA, he split his career primarily between contra... more
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    Kelliann Marrero
    Program Resource Analyst
    Kelliann Marrero has been employed at NASA’s Jet Propulsion Laboratory since 2000. She started her career at the lab as a travel coordinator while earning her bachelor’s in business administration from the University of La Verne, which she completed with summa cum laude honors. She then moved onto project accounting while earning her master’s in business administration with a concentration in supply-chain management. Upon completion of her MBA, she moved onto a position as a project re... more
  • Amy Strand
    Amy Strand
    Project Schedule Analyst
    Amy Strand has been employed at NASA’s Jet Propulsion Laboratory since 2013 and has provided scheduling support to 7x, 8x, and 9x departments throughout her career at JPL. She has over 26 years of experience outside of JPL in program/project management, cost and scheduling, earned value and cash flow analysis in an engineering/construction environment. Amy has proven communication skills to support many of JPL’s business processes.
  • Jennifer Gregory
    Jennifer Gregory

    Business Administrator
    Jennifer Gregory has been employed at NASA’s Jet Propulsion Laboratory since 1998 and has provided administrative support to several departments throughout her career. Among these were Interferometry and Large Optics, the Space Interferometry Mission and JPL’s special program DOD activities. In 2015, Ms. Gregory eagerly joined the Exoplanet Exploration Program Office. She enjoys being a part of NASA’s vision and development of technology and missions that enable the search for life in the universe.

  • Karla Miller
    Karla Miller

    Executive Staff Assistant
    Karla Miller has worked at JPL since 1993, first as a contractor, then becoming permanent in 1995. She has provided administrative support in several areas beginning with the Low Temperature Science & Engineering group, CHeX (Confined Helium Experiment) project, and the SESPD (Space Engineering & Science Program Division). She has worked in her present position for over 16 years, when it was called the “Origins” and “Navigator” Program Office. She is fascinated when planets are discovered and enjoys being part of a remarkable group, a team of experts searching for life on other planets.

  • Rebecca Gonzalez
    Rebecca Gonzalez

    Program Staff Assistant
    Rebecca Gonzalez has worked at JPL and in the Exoplanet Exploration Program office since 2018. Her responsibilities are split between providing administrative support to the program office, and the public engagement areas of Exoplanet Communications and the AstroComms. Prior to coming to JPL, she was the executive assistant to the chief information officer of the city of Pasadena. Ms. Gonzalez holds a Bachelor of Science degree in business management from the University of Phoenix. She enjoys being part of the mission to search for planets beyond our solar system, characterize them, and look for life among the stars.

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    Jennifer Blumberg
    Executive Staff Coordinator
    Jennifer Blumberg is currently the Executive Staff Coordinator for the Astronomy and Physics Directorate (APD). Previously, she was the APD staff assistant to the Chief Engineer, Chief Scientist, Chief Technologist, and Business Office. Since Jennifer has been an employee at NASA's Jet Propulsion Laboratory since 2002, she has held administrative roles throughout the Astronomy and Physics Directorate as an Administrative Assistant to National Security Program Office, Project Administrative Assist... more
  • Pat Brennan
    Pat Brennan
    Science Writer
    Pat Brennan is a science writer for NASA's Exoplanet Exploration Program, and also for the NASA Sea Level Portal. He writes feature stories about exoplanet discoveries and helps develop a variety of public engagement content, from info-graphics to conference banner stands and even provided text for a recent exoplanet travel poster. Mr. Brennan joined JPL in 2015 after a 30-year career as a newspaper journalist. He has a bachelor's degree in journalism from the University of Arizona.
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    Chelsea Gohd
    Universe Public Engagement Specialist
    Chelsea "Foxanne" Gohd is a Universe Public Engagement Specialist at NASA's Jet Propulsion Laboratory. With her experience as a science communicator and writer, she works to make science accessible for a public audience through a creative variety of content. Previously, she worked as a senior writer at Space.com where she wrote newsworthy articles and longer features on science topics ranging from climate change to exoplanet exploration and huma... more