Planetscope: An Exoplanet Coronagraph on a Balloon Platform

摘要

Direct detection of mature exoplanets is possible using a visible-wavelength telescope and coronagraph in the stratosphere. We analyze two sources of dynamic wavefront perturbations: turbulence in the free atmosphere and locally generated turbulence. We find that they are expected to have relatively small effects on the wavefront. We find that neither source should limit observations at 10~(-9) contrast levels for planet-star separations of 0.5 arcsec. On this basis, we expect that it is feasible to image and characterize several known radial-velocity exoplanets.