Eight years ago, a group of eight high schoolers in central Japan attached a smartphone equipped with two cameras and a GPS to a weather balloon and let it go. It went up and up and... disappeared. In November this year, the cameras were found in the woods near Tokyo, revealing their 32-kilometer trip into the stratosphere and the blue curve of Earth against the blackness of space. The eight teens launched the weather balloon in November 2012 as part of a class project at their high school in Iida, Nagano Prefecture. To avoid dense settlements and airports, the students released the balloon in the town of Eiheiji, Fukui Prefecture, two prefectures to the west of Nagano. They expected the smartphone rig to parachute back to Earth after the balloon burst in the stratosphere, landing in or around Moka, Tochigi Prefecture, north of Tokyo. But things did not go to plan. A frame grab from a video taken from a balloon released by a group of Nagano Prefecture high school students in November 2012 shows the curve of the Earth. (Image courtesy of Tomoyuki Fukuzawa) At around the 1,000-meter altitude mark, the students lost the balloon's signal, so they had no idea where it was, or would be when the balloon popped. They calculated that the smartphone may have ended up somewhere around Iimori ridge in the town of Tokigawa, Saitama Prefecture, north of Tokyo. However, they could not find the apparatus, and went on to graduate thinking it was lost. [...]