Two University of Sheffield students have recorded a video of the Earth from the edge of space, using homemade equipment and on a shoestring budget.

Alex Baker and Chris Rose, both PhD students from the University’s Department of Mechanical Engineering, sent a helium-filled balloon with two video cameras and a tracking device up into the atmosphere, filming video and taking pictures as it went.

The balloon was launched from Ashborne, Derbyshire on 17 December 2010, and was in flight for approximately two hours and 50 minutes, before landing in a field in Strethall, Cambridgeshire, a journey of over 100 miles. The location, which is Chris’ home town, was chosen specifically, as it was predicted that launching there would result in the device landing in a rural area.

The video footage, which lasts for two hours, shows the balloon being launched at sunrise and rapidly climbing above the clouds, filming the ground below and eventually showing the curvature of the Earth’s atmosphere. The balloon, after swelling to many times its original size, eventually burst, allowing the parachute to open and the box to descend back to Earth. It is thought that at its maximum height, the balloon reached an altitude of 37km.

The device, which was built by Alex and Chris in their spare time, consisted of a foam box, a parachute for the descent and the balloon. The electronic equipment had to be well insulated due to the extremely cold temperatures at such high altitudes, with duct tape and a small heat pad used to keep the cameras warm. A GPS tracking system, CATtrack, sent a text displaying its location when rung, allowing it to be collected. However, the whole device cost only £350 to build.

The video also shows the box being built from scratch, and the journey to collect the device from a snowy field in Cambridgeshire.

Dr Edward Hanna, from the University’s Department of Geography, said: “It’s a spectacular video. You can see the sky darkening as the balloon ascends, due to less molecular scattering as the atmosphere becomes thinner. In addition, the video also shows the curvature of the Earth, which becomes more apparent the higher the balloon climbs, and amazing cloud formations which we can see from above.

The device made it into the mid-stratosphere, where the atmospheric pressure is less than one per cent than that at the surface, and temperatures would have been around – 30 C to – 40 C. However, the lowest temperature would have been midway through the ascent, at around the 10km mark, when it would have been around minus 50 degrees Celsius.”

Alex said: “We decided to do it essentially because we’d seen it was possible. Although we tried to plan for as much as we could, we were still very lucky that things worked in our favour on the day.

We were concerned when we didn’t receive a signal from the GPS tracker on the device during the whole flight, as it turned out only to work when on the ground. Even once it landed we struggled, as putting the coordinates into the Iphone only got us to the nearest road.”

Chris said: “We wanted to do a low budget attempt, so we couldn’t be happier with the results, and wanted to share the whole experience from start to finish with others. It’s also a good opportunity to show that this could be undertaken by anyone, even with a relatively small budget.”

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