Shoestring-budget experiment records curvature of Earth

A homemade experiment made on a shoestring budget has recorded a video of the Earth from the outer edge of space.

Image taken from the video footage at an altitude of around 35km

Chris Rose and Alex Baker, two PhD students from the University of Sheffield’s department of mechanical engineering sent a helium-filled balloon with two video cameras and a tracking device up into the atmosphere to record videos and take pictures.

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

During its flight, the balloon recorded two hours of video which showed the balloon being launched and rapidly climbing above the clouds, filming the ground below and eventually the curvature of the Earth.

“It’s a spectacular video,” said Dr Edward Hanna from the department of geography. “You can see the sky darkening as the balloon ascends, due to less molecular scattering as the atmosphere becomes thinner.”

“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,” he added.

The balloon was launched from Derbyshire at sunrise and almost three hours later it landed over 100 miles away in Cambridgeshire. The device made it into the mid-stratosphere reaching an estimated maximum altitude of 37km.

The device – built by the pair in their spare time at a cost of £350 – consisted of a foam box, a parachute for the decent and the balloon. The device was insulated with duct tape and included a heat pad to protect the cameras against the extreme cold – between -30°C and -40°C – at high altitude. A GPS tracking system allowed the scientists find the device when it landed.

“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,” Rose said. “It’s a good opportunity to show that this could be undertaken by anyone, even with a relatively small budget.”