COIMBATORE: In a hands-on experiment that took their classroom learning to the edge of space, students from 11 government middle schools in Periyanaickenpalayam. It remained airborne for nearly three hours before descending at a location about 80 km from the launch site, where a recovery team retrieved it.The payload was equipped with sensors to measure temperature, atmospheric pressure and humidity, along with a passive particle trap to collect airborne particulate matter..