The Journal of Astronomical Telescopes, Instruments, and Systems (JATIS) recently published a special section on the Wide-Field Infrared Survey Telescope (WFIRST) coronagraph instrument. WFIRST is a space-based telescope mission that NASA plans to launch sometime after the James Webb Space Telescope launches in 2018.
Twenty-two peer-reviewed papers are featured in the special section of the SPIE journal, which had as guest editors SPIE member Olivier Guyon of University of Arizona and Subaru Telescope (USA) and Motohide Tamura of University of Tokyo and National Astronomical Observatory of Japan.
Guyon and Tamura say that the space coronagraph instrument will be an important step in expanding the capability of direct imaging and spectroscopy of extrasolar planets (exoplanets) and eventually enable “imaging and spectroscopic study of super-Earths and potentially habitable Earth-like planets.”
Artist’s illustration of NASA’s WFIRST observatory.
Courtesy Conceptual Image Lab at NASA Goddard Space Flight Center.
Papers in the special section describe the instrument that will be used to conduct a wide-field NIR survey of nearby exoplanets. WFIRST will be a 6-year mission and utilize an existing 2.4-m telescope (7.9 feet, the same size as the Hubble Space Telescope’s primary mirror) that will likely operate from geosynchronous orbit.
The papers provide an overview of coronagraph technologies, high-contrast imaging and spectroscopy, wavefront sensing and control, operations, algorithms, modeling, and data analysis. The papers also cover exoplanet yield statistics, simulation results, occulting mask design, and fabrication.
While the system’s centrally obscured pupil complicates the design of a high-contrast coronagraph, the editors say scientists expect it to “achieve the detection contrast to image an exoplanet as near as the 3rd Airy ring of the point-spread function in broadband light, allowing for the first time reflected-light imaging and spectroscopic characterization of exoplanets.”
Pointing to a field of view expected to be 100 times larger than Hubble’s, NASA says its next major astrophysics observatory will explore the evolution of the cosmos and aid researchers in their efforts to unravel the secrets of dark energy and dark matter.
Read more in the JATIS special section on WFIRST-AFTA Coronagraphs.