Two University of Sheffield engineering students have recorded a video of the Earth from the edge of space using homemade equipment built on a shoestring budget, proving that you don’t need NASA-scale finances to have a go yourself.
Alex Baker and Chris Rose, both PhD students from the university’s Department of Mechanical Engineering, sent a helium-filled ‘weather balloon’ with two video cameras and a tracking device up into the atmosphere, filming video and taking pictures as it went.
The project came about as a challenge for the students, who wanted to see how cheaply it could be done and to prove that its possible for anyone to achieve.
“We’d seen that it was possible and so we wanted to see just how cheaply it could be done and produce a video showing that anyone can do it,” says Baker. “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.”
Doing the research
“Once the idea was in our heads to do the project, it was a question of doing a little research, finding a cheap tracking device: we settled on a CATtrack, a device used for finding AWOL pets, and deciding how to insulate against the harsh temperatures it would face,” continues Rose. “We found a website that allowed landing predictions to be calculated based on current wind data, so this was useful in securing a landing site that wasn’t in the sea or a city,” he notes.
The components and cost
Built in their spare time, the whole device only cost £350 to complete. It 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. The GPS tracking system sent a text displaying its location when rung, allowing it to be collected.
“The main costs in the build were the balloon, the tracker and the helium,” says Rose. “Everything else could be sourced as cheaply as possible. For example, foam came out of a bin and one camera was an old used compact beastie.”
Reaching near space
The balloon was launched from Ashborne, Derbyshire 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 launch site was in Rose’s home town, 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 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 0C to -40 0C. However, the lowest temperature would have been midway through the ascent, at around the 10km mark, when it would have been around -50 0C.
Although things eventually went to plan, the team did have one slight worry – the CATtrack GPS system didn’t work as planned.
“The CATtrack failed to work once the device was airborne. We guess they didn't expect pets to wander off into space,” laughs Baker. “Fortunately, we received a signal again once the device was back on Earth. Even once it landed we struggled, as putting the coordinates into the iPhone only got us to the nearest road.”
Everyone at the university was enthusiastic about the students’ success and their supervisor even commissioned a picture from the peak altitude of the flight, which is now hanging up in the department.
Although they haven't had a knock on the door from NASA, Baker and Rose aren’t planning to hang up their experiment jackets just yet.
“No word from NASA or ESA yet, but we'd love to hear from them! We’re not entirely sure as of yet what will be next, though this has certainly whet our appetite to do something else, whether a new project, or maybe a repeat with a higher budget to really see what is possible from balloon near space flight,” Baker concludes.