During the Koppelting grassroots festival we launched a balloon with some sensors and a (LoRa) radio to send the results live back to us. It contained an IR light sensor and an Infrared thermopile sensor looking downward, to see if we can detect a change in the absorbed/reflected IR radiation in the atmosphere with increasing altitude. In addition, we add an upward facing UV-A/B sensor. We reached an altitude of 38.7 km, and reached a gateway 702 km away fro the balloon.
Results and access to the data at: http://koppelting.ltcm.net