With just $800 in basic equipment, researchers found a stunning variety of data—including thousands of T-Mobile users’ calls and texts and even US military communications—sent by satellites unencrypted.

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 eavesdropping, a team of researchers at UC San Diego and the University of Maryland revealed today in a study that will likely resonate across the cybersecurity industry, telecom firms, and inside military and intelligence agencies worldwide.