Opto-mechanical design of the ESCAPE Small Explorer: An EUV spectrograph for exoplanet host star irradiance and CME activity

Brian T. Fleming, Kevin France, Timothy Hellickson, Tom Patton, Bryce Unruh, Nicholas Kruczek, David McKenzie, Patrick Champey, Peter Cheimets, Edward Hertz, Suzanne Romaine, Randall McEntaffer, Fabien Grise, Drew Miles, Oswald Siegmund, Jason McPhate, James Green, Matthew Beasley

Research output: Chapter in Book/Report/Conference proceedingConference contribution


The University of Colorado led Extreme-ultraviolet Stellar Characterization for Atmospheric Physics and Evolution (ESCAPE) small explorer mission concept is designed to measure the extreme-and far-ultraviolet (EUV; 80-560 A, 600-825 A, FUV; 1280-1650 A) irradiance and are activity of exoplanet host stars; essential measurements for assessing the stability of rocky planet atmospheres in the liquid-water habitable zone. The ESCAPE design consists of a fixed optical configuration with a grazing incidence Gregorian, or "Hetterick-Bowyer", telescope feeding grazing and normal incidence spectroscopic channels. The telescope is provided by a joint NASA Marshall Space Flight Center and Smithsonian Astrophysics Observatory team. The grazing incidence gratings have a radial profile and are ruled into single-crystal silicon using electron-beam lithography in the nanofabrication laboratory at Pennsylvania State University. Normal incidence gratings have aberration correcting holographic solutions and are supplied by Horiba Jobin Yvon. Spectra are imaged onto a curved microchannel plate detector supplied by the University of California, Berkeley. ESCAPE utilizes the Ball Aerospace BCP spacecraft. The simple, fixed configuration design of ESCAPE is projected to exceed the effective area of the last major EUV astrophysics spectrograph, EUV E-DS/S, by more than a factor of 50, providing unprecedented sensitivity in this essential bandpass for exoplanet host-star characterization. We report on the ESCAPE design, projected performance and mission implementation plan, as well as the trade studies carried out over Phase A to scope the first NASA EUV astrophysics mission in nearly 30 years. If selected, ESCAPE will launch in Fall 2025.

Original languageEnglish (US)
Title of host publicationUV, X-Ray, and Gamma-Ray Space Instrumentation for Astronomy XXII
EditorsOswald H. Siegmund
ISBN (Electronic)9781510644809
StatePublished - 2021
EventUV, X-Ray, and Gamma-Ray Space Instrumentation for Astronomy XXII 2021 - San Diego, United States
Duration: Aug 1 2021Aug 5 2021

Publication series

NameProceedings of SPIE - The International Society for Optical Engineering
ISSN (Print)0277-786X
ISSN (Electronic)1996-756X


ConferenceUV, X-Ray, and Gamma-Ray Space Instrumentation for Astronomy XXII 2021
Country/TerritoryUnited States
CitySan Diego

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering

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