Overview of the 4m baseline architecture concept of the habitable exoplanet imaging mission (HabEx) study

The Habitable Exoplanet Imaging Mission (HabEx) Study is one of four studies sponsored by NASA for consideration by the 2020 Decadal Survey Committee as a potential flagship astrophysics mission. A primary science directive of HabEx would be to image and characterize potential habitable exoplanets around nearby stars. As such, the baseline design of the HabEx observatory includes two complimentary starlight suppression systems that reveal the reflected light from the exoplanet – an internal coronagraph instrument, and an external, formation-flying starshade occulter. In addition, two general astrophysics instruments are baselined: a high-resolution ultraviolet spectrograph, and an ultraviolet, visible, and near-infrared (UV/Vis/NIR), multi-purpose, wide-field imaging camera and spectrograph. In this paper, we present the baseline architecture concept for a 4m HabEx telescope, including key requirements and a description of the mission and payload designs.