HiCIBaS: A precursor mission for high contrast imaging balloon systems

Even though space-based astronomical observations provides valuable data in optical regimes that are not possible on ground, they are still scarce and difficult to plan because of the high cost that is involved with space-based instrumentation. Flying scientific instruments aboard sub-orbital balloons can be achieve at a fraction of the cost. HiCIBaS, the High-Contrast Imaging Balloon System, provides a platform to develop instrumentation and imaging techniques for future balloon-borne high-contrast coronagraph to detect and characterize extrasolar planets.

HiCIBaS consists of an off-the-shelf 14-inch Schmidt-Cassegrain telescope, a custom Nasmyth mount and a high-contrast instrument. The optical payload will be flown at an altitude of 36 km aboard a pointed multi-instrument gondola (CARMEN) provided by CNES using CSA's Stratos program from Timmins, Ontario (Canada). High-contrast imaging becomes interesting at this altitude because there is only 1% of the atmosphere left to induce wavefront error. The gondola can be stabilized in azimuth to ±1 deg, so the front-end optics include two cameras used for a coarse pointing system. The telescope mount can rotate to ±20 degrees in azimuth and from -20 degrees to +60 degrees in elevation. The optical payload consists of two instruments, a pyramidal-style low-order wavefront sensor (LOWFS) and a coronagraphic wavefront sensor (CWS). Both the telescope mount and the optical bench were designed by the HiCIBaS team in collaboration with OMP Inc, science EMCCD's were provided by Nüvü Caméras and the segmented deformable mirror was provided by Iris AO Inc.

HiCIBaS launch is scheduled between August 13^th and August 25^th, just after 23h00 local time. The mission will be in two parts, a night and an early-day phase. During the night phase Cappella will be used to record data on atmospheric turbulence and test the new technology used on this first flight. During the day, the objective will mainly be to obtain data on the luminosity of the background compared to Polaris, the second target star.