Origins Space Telescope (Origins): The Mid-Infrared Spectrometer (Camera) Transit Spectrometer (MISC-T)
Abstract
The Origins Space Telescope (Origins) is one of four flagship mission concepts funded by NASA for consideration in the 2020 Astrophysics Decadal Review. Origins operates in the wavelength range 2.8 to 588 microns and is more than three orders of magnitude more sensitive than its predecessors due to its large, cold (4.5 K) telescope and advanced instruments. Three science instruments provide the powerful new spectroscopic and imaging capabilities required to achieve the Origins science objectives and enable community-driven discovery science. One instrument, the Mid-Infrared Spectrometer (Camera) Transit Spectrometer (MISC-T) will observe at the shortest wavelengths of any of these instruments, from 2.8 to 20 microns and will provide ultra-stable spectroscopic measurements of biosignatures in habitable worlds in primary and secondary exoplanet transits. This broad simultaneous wavelength coverage allows measurements of the surface temperatures of the exoplanets as well as detections of molecules O3, CH4, H2O, CO2, and N2O at Earth-levels, should they exist in an exoplanet atmosphere. The optical design employs an Tip-tilt sensor (MISC-TTS) that uses reflected light from a Lyot-Coronagraph focal plane mask to determine the position of the PSF centroid on the detector plane. MISC-T has a densified pupil spectrometer design with R~50-300 and is capable of exoplanet transit and emission spectroscopy with spectro-photometric stability as low as 5 ppm. This allows at least 3.6-sigma detections of all the lines of interest in 85 transits of a K = 9.8 magnitude M-star. During the concept study, an additional MISC mid-infrared camera and spectrometer (R~300 over 5 to 28 microns) was studied and is described in the Origins report as an upscope option, further enhancing the Origins mission's scientific capabilities. This presentation covers the motivation, design, and expected performance of MISC-T when observing exoplanet transits of M stars. We thank NASA Headquarters, GSFC, Caltech/JPL, Ames, IPAC , STScI and industry partners Ball Aerospace, Northrop-Grumman, Harris, and Lockheed-Martin for their generous support of the Origins study. To learn more about Origins see our websites (https://origins.ipac.caltech.edu and https://asd.gsfc.nasa.gov/firs/) and report (https://asd.gsfc.nasa.gov/firs/docs/OriginsVolume1MissionConceptStudyReport.pdf).
- Publication:
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American Astronomical Society Meeting Abstracts #235
- Pub Date:
- January 2020
- Bibcode:
- 2020AAS...23517104R