In December 2010, Scott (E6C - Echo Six Charlie), Steve (Waya) and Tanya (Woyi), geocachers from North Carolina, launched a geocache into space. Well, technically it's called near space, but it went very high and very far.
The idea came from a father and son who launched an iPhone tied to a balloon and posted the video on the web. E6C thought, "Well if they can do it, we can too... and do it better!"
How do you make a geocache that can go into space (well almost into space)? The first thing to work out, is how much the payload is going to weigh.
To record the event they used a Kodak Zi6 camera (like a Flip video), a Samsung Joy cell phone and a still camera. A Spot GPS was used to track the balloon's progress. The advantage of a Spot is that it communicates via satellite, so even if the balloon lands out of cell phone range, it can still transmit its location. Including the cache container and parachute, the total weight of the payload was about 4 lbs (~2kg).
Parachute? Why do you need a parachute? Well they were concerned about a 4 lb payload coming down and hitting someone. Since E6C works in the military he was able to acquire an old 6 ft diameter drogue 'chute that attaches to a spring in the main parachute pack.
The next challenge was to figure out how much helium to use for the weight of payload. They calculated the buoyancy of helium needed for the weight, and then how much volume that helium would fill at 100,000 ft. This produced a result that showed that they needed a balloon of 19ft in diameter. So they went ahead and purchased a 19ft weather balloon from Scientific Sales.
The balloon is designed to burst when it reaches that diameter, and that determines the maximum altitude that can be achieved.
The balloon with the payload was launched on 18 December at 9:33AM near Fayetteville, North Carolina. It climbed at about 1600 feet/minute and took almost 1 hour to achieve an altitude of 101,001 feet before the balloon burst. It took about the same time to fall back to earth.
During the climb and descent the balloon travelled 124 miles (198 km) and landed on in a small forest behind someone's place. The group who launched the balloon arrived at the owner's front door. Apparently his eyes lit up when he heard the story and took them out the back of his property to locate it.
It had come down safely and was hanging from a tree about 8ft off the ground.
The cache is now permanently located there and you can go and find it. The cache code is GC2JPJJ. It's listed as multi. You are supposed to go to the launch site where there is a plaque that gives the final co-ords. Alternatively you can watch the video which shows the final co-0rdinates. It is on private property, but permission has been graciously granted by the owner. Just stop by the house (at reasonable hours) and let Mr. Hutchins know you are going through his backyard. Balloon remains are at the GZ for posterity (with permission from the owner, too).
The official website of the project is here: http://gaia.terrasunder.org/
Here is the interview that I did with Scott (E6C) where he talks about how to launch a geocache into space ... WITHOUT a Space Shuttle!