Satellites beam data down to the Earth all around us, all the time. So you might expect that those space-based radio communications would be encrypted to prevent any snoop with a satellite dish from accessing the torrent of secret information constantly raining from the sky. You would, to a surprising and troubling degree, be wrong.Roughly half of geostationary satellite signals, many carrying sensitive consumer, corporate, and government communications, have been left entirely vulnerable to eav...