It is Kjell Lindgren who holds an amateur radio licence, callsign KO5MOS. Kjell would have been operating the ISS amateur radio station in the Columbus module using the station callsign NA1SS. See AMSAT-UK at http://amsat-uk.org/2015/08/05/uk-radio-hams-iss-contact-in-the-press/
Biting the hand that feeds IT
