British pop star Sophie Ellis-Bextor seized a "once in a lifetime" opportunity to experience zero gravity for an out-of-this-world photoshoot. The singer was asked to shoot a commercial for British snack firm Walkers while floating onboard a zero gravity flight. Ellis-Bextor jumped at the chance to experience weightlessness, flying to Houston, Texas to take part in the project, but she admits that she quickly discovered that filming in zero gravity is not easy. She tells Britain's Hello! magazine, "I thought it would be a bit like swimming underwater, but it's a lot more serene and incredibly passive, so you can't be so directional. When I was having my picture taken, they kept having to grab my foot and spin me the other way round. "It was a once in a lifetime thing to do. I can't really compare it to anything I've done before. It felt really lovely. Quite addictive." The singer follows in the footsteps of model Kate Upton, who recently signed up for a zero gravity photoshoot for the 2014 Sports Illustrated Swimsuit Issue.