In January 2013, the NASA Astrophysics Division initiated the formation of two Science and Technology Definition Teams (STDTs) to study probe-scale (cost less than $1B) mission concepts for the direct detection of extrasolar planets orbiting nearby stars. The STDTs were supported by a Design Team staffed by the Exoplanet Exploration Program. One STDT studied a concept based on a telescope with an internal coronagraph capable of generating the ultra-high contrast images needed for planet detection. This concept borrowed a great deal from the sub $1B Kepler design to control cost. The second study looked at two concepts using a pair of spacecraft flying in formation - a telescope and an external occulter (starshade). The first concept contained a complete end-to-end, two-spacecraft concept using commercial busses and a commercial telescope, at a cost slightly above the $1B target. The second starshade concept launched only the starshade spacecraft as an add-on to an existing space telescope mission. This second concept was significantly under the probe-class cost target. These studies are now complete and are summarized in their Final Reports, now available through the links below on this page.

STDT Charter

As a follow on to the successful Probe-class Direct Imaging concept studies, the NASA Astrophysics Division (APD) has released a new charter to extend the Coronagraph and Starshade concept exploration to designs outside of the Probe-class cost and programmatic requirements. Like the Probe-class studies, these new studies are intended to provide technical design information to the general exoplanet research community in advance of the 2020 Decadal Survey exoplanet concept studies. These “extended studies” will continue to be supported by the members of the original Probe study STDTs that are able to continue in their original capacity, and as before, the STDTs will receive design support through the Exoplanet Exploration Program (ExEP). Due to the rapidly approaching start of the 2020 Decadal Survey studies, detailed written reports such as those produced for the Probe studies will not be possible; two publicly released presentations will be the final products for these new studies. The presentations will be delivered to APD in December 2015 with public versions released through this ExEP web portal shortly thereafter.

Charter for the Science and Technology Definition Team (STDT) for the Extended Study Exoplanet Direct Imaging Mission Concepts

STDT Final Reports



NASA Advisory Council’s Astrophysics Subcommittee (APS) Presentations

March 17-18

Committee on Astronomy and Astrophysics (CAA) Meeting

March 3-5, 2014

Exo-S STDT Pages

Exo-C STDT Pages

Dear Colleague Letter 

External Occulter STDT Membership
5/2/2013 - Chair: Sara Seager (MIT)

Internal Coronagraph STDT Membership
5/2/2013 - Chair: Karl Stapelfeldt (GSFC)

STDT Charter

STDT Meetings

  • First joint meeting: July 1-2, 2013 at Goddard Space Flight Center, Greenbelt, MD
  • Second joint meeting: September 11-12, 2013 at MIT, Cambridge, MA
  • Third joint meeting: November 13-15 2013 at JPL, Pasadena, CA
  • Fourth Meeting (Exo-S): January 28-29, 2014, Washington DC
  • Fourth Meeting (Exo-C): February 3-5, 2014, JPL, Pasadena CA
  • Fifth Meeting (Exo-S): June 10-11, 2014, Chicago, IL
  • Fifth Meeting (Exo-C): June 17-19, 2014, NASA Ames, Mountain View, CA
  • Sixth Meeting (Exo-S): August 14-15, 2014, JPL
  • Sixth Meeting (Exo-C): September 15-16, 2014, GSFC
  • Seventh Meeting (Exo-C): November 3-5, 2014, JPL
  • Seventh Meeting (Exo-S): November 4-5, 2014, New York City