The Thermometer

When I started planning the project, I wanted to get some data from it back. One sort of data was the GPS and altitude information, another was temperature. The balloon with its intended reach up to 30km above sea level promised data from a not so ordinary and regularly achievable environment.

The device I eventually used was Comet System's S0122 datalogger. It is able to measure and record temperatures every 10 seconds from both an inbuilt sensor and an external probe in the range of -50 to +150°C. Thus I would have a record of the outside temperature with respect to altitude and a record of to what conditions was the inner equipment exposed.

The idealized International Standard Atmosphere model states a gradual decrease in temperature from the sea level's 15°C  to -56.5°C in the altitude of 11km. Then a stable temperature from 11 to 20km followed by a gradual increase in temperature from 20 to 47km altitude. That promised a proper test for the payload box and the equipment inside.