On November 16, in Prague, Czech Republic, 13 thousand players and their families watched the launch of a balloon into the stratosphere. They witnessed the world’s first Stratocaching event, which combines near-space flight and a geocaching game. The video from the flight to stratosphere and back was broadcast live on Technet.cz. Hundreds of thousands of people watched the unique dramatic moments broadcasted from 30 000 meters (100 000 feet) from above.
At its highest point of the journey, the gondola, named Dropion, released its twelve devices carrying GPS trackers. These then glided down like a winged maple seed.
Players on the ground participated in a massive treasure hunt, looking for the coordinates on their smartphones, or relying on their own calculations, intuition and luck. So far five out of the twelve stratoseeds have been found, and the hunt continues. This experiment also introduced some details of near-space physics, meteorology and technology. For the enthusiastic fans, space was quite literally only a touch away.
Preparations Technical delays, successful video stream
Launching high-altitude balloons is nothing special. At Prague's Hydrometheorological Institute, meteorologists do it three times a day. Unlike traditional balloons soaring to the stratosphere, this one carried a high-tech load to document the ride. The Dropion had two HD cameras (GoPro and Axis) to capture the start of a new kind of geocaching game.
Geocaching has a strong fan-base in the Czech Republic, ranking 4th in the world on Geocaching.com, so it was to be expected to gain an audience. Still, organizers were a bit surprised by the splash this game caused. On the launch site, hundreds fans watched the countdown, with tens of thousands more watching it live online at Technet.cz. Overall, more than 200 thousand people watched the live stream.
While the balloon was being filled with 10 000 litres of helium, children were enjoying the fact that adults are, for a moment, just as wide-eye enthusiastic as them.
After 80-minute delay, it was time for the final countdown.
Launch Soaring high, taking pictures of a jet-plane
At 10:24 AM (UTC+1), the coundown was completed and the balloon soared up, where sky was not the limit.
The balloon flew upwards, still being visible for several minutes.
After the launch, spectators disappeared quickly. The treasure hunt just started. Using their predictions, calculations or intuition, they took off on a chase to the anticipated landing spots.
Video Connection to stratosphere established
The team of broadcast specialists faced the major challenge of maintaining the video stream broadcasted from the Dropion's Axis camera.
Not only were they able to re-establish the connection manually several times, but they also helped the viewers witness several interesting sights, including the Emirates Airbus A380 airplane flying from Dubai to New York. The Dropion was properly registred with the aviation authorities for civilian flights.
At 11:27, the Dropion was 26 000 m (89 000 ft) above the ground, enduring the temperature of -32 °C (-26 °F). An embedded system on the main computer controlled the timing of the small explosion used to release the seeds. The scheduled explosion, which happened at approximately 11:40, released the stratoseeds to the ground.
A few moments later, the balloon was also released and Dropion started falling to the ground. In the virtual absence of air in the stratosphere, it plummeted at over 200 km/h (over 125 mph) , but soon the parachute met with the air resistance and slowed it down to its soft landing speed.
Landing Busy times in a quiet village
Meanwhile, numerous enthusiasts from the Radio Club used their prediction models, radio equipment and locations available on the Stratocaching website as they tried to pinpoint the landing site. Organizers from the movement Žádná Věda (Czech for "Not Rocket Science") included special features to the game so that radio enthusiasts could have extra challanges. Following their cars and listening to their PTT conversations filled with experienced technical slang, the search might seem like a military-organized rescue mission.
After a change of wind direction, cars took a shortcut onto a dusty path in order to keep visual contact with the Dropion. At 12:21, it landed at the garden of a family house in the small vilage of Cerhovice, 50 km (31 miles) from its launch.
The owner of the house was surprised to see two dozens cars in his usually quiet street. As the enthusiasts explained the game and asked him for permission to retrieve an object that dropped from near-space into his garden, he chuckled: "Sure, come in, you all. You are lucky our dog is inside. Had he been outside, there would have been nothing left of it to retrieve."
The family from the house took pictures with the alien object landing on their garden. They also offered the happy group of founders kolache, typical Czech pie.
Stratoseeds Most GPS trackers didn't survive the temperature
The game was not over yet. The stratoseeds, designed to fall at 8 km/h (5 mph), gliding down like a winged maple seed.
The design of the seeds is inspired by nature. Each seed weighed 93 grams (3.2 oz) and contained a GPS/GSM tracker to allow the players to easily locate them on the ground.
In the original plan, players were supposed to use special mobile app to locate the seeds and claim their prizes. Unfortunately, the developer was not able to supply a bug-free app on time, so players had to use the website for locations and SMS, email or phone to claim their discoveries.
One of the lucky discoverers of the second stratoseed.
Out of the twelve seeds, only five were found during the first day. A malfunction of the GPS/ GSM trackers meant most of the stratoseeds did not survive the extreme temperature of the stratosphere. Some seeds were found through chance, other by enthusiasts who used personal helicopters to look for shiny objects in the fields.
Hundreds of cars were on the site of discovery of the seeds.
One of the stratoseeds was spotted in the Berounka river, but no one wanted to brave the cold temperatures to retrieve it. Other seeds are yet to be discovered.
Summary Amazing experiment with room for improvement
The event was not without its detractors. Some expressed regret about the malfunctioning stratoseeds and the buggy mobile app. The website was often swamped with requests and due to the massive popularity of the game, the mobile data connection was often down on the countryside.
The organizers consider it a success overall, though. "The demand for the game was a pleasant surprise and the fact that the radio experts were able to follow the Dropion and maintain the video streaming is really impressive," said Jan Kužník, editor in chief of Technet.cz. "Plus, the weather was amazing, which made the video even better than expected."
"The demand for this new kind of geocaching is clear. We seem to have no choice but to go on with this," said Ivan Sobička from Žádná věda. The radio enthusiasts, the most active group throughout the day, would agree. Although they failed to retreive the radioseed due to its low battery, they are already planning how they will search for the seeds from space in the future. "Geocaching is here to stay," declared one. "It's something else."