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It feels as if I’m hallucinating: as I lie on the floor, the ceiling suddenly sinks towards me and the walls begin to tilt at an impossible angle. It is my first experience of zero gravity on an European Space Agency (Esa) parabolic flight. In theory I know what is going on, but my brain just cannot grasp that it is actually me that is floating, that I’m suspended midair.
I am accompanying Britain’s first female Esa astronaut, Rosemary Coogan, on the flight as part of her zero gravity training for a potential six-month deployment to the International Space Station. During the three-hour flight, sometimes referred to as the vomit comet, the plane will trace out 31 parabolas – soaring arcs in the sky.
As we await take-off, any nerves I felt have been replaced by excitement, my confidence bolstered by the spacesuit I have been issued and a generous injection of antinausea medication.
The plane will not, literally, be exiting the Earth’s gravitational sphere. Instead, it follows a rollercoaster trajectory designed to simulate zero gravity. Each parabola begins with a steep climb, with the plane reaching a 50-degree angle and close to its maximum speed. At this point, the engines are all but cut and the plane and everyone within are slingshotted into a freefall trajectory. Gravity still exists in the outside world, but not within the plane’s frame of reference. After 22 seconds, the engines rev up again, the plane nosedives and anyone airbound will be dumped unceremoniously back on the floor.
During the first half of the flight, I am assigned the “free floating area” a netted cage with a padded floor at the back of the plane, to try out some basic astronaut mobility skills, while Coogan is learning to use an experimental glove box.
During the “pull up” phase, we experience hyper-gravity. My body is crushed into the floor, hands feel like lead and then the pilot counts down over the intercom: “Three, two, one. Injection”. The engines cut, a hush descends, and weightlessness kicks in.
The first instinct is to “swim” but I find myself flailing ridiculously in midair. Bouncing off the walls like a balloon proves more effective and soon I’m happily turning somersaults.
“Let go of the notion of up and down,” says Neil Melville, Esa’s parabolic flight coordinator, as we walk up the wall, across the ceiling and shake hands while suspended upside down.
Temporarily gaining the ability to fly is obviously a major draw of the whole experience. But the inner sensation of weightlessness is, unexpectedly, just as extraordinary. The internal organs lift, blood flows effortlessly to the brain, a sense of serene disembodiment takes over.
“You talk to astronauts about these things and, especially if they’ve been looking out of a window for a long time, they forget that they’ve got a body,” Melville says.
The aircraft, an adapted Airbus, was once Angela Merkel’s government plane: it is old enough to have manual controls (a modern commercial plane would automatically block a pilot attempting a 50-degree climb), but with few enough flying hours to be in robust condition. The intensity of forces during the parabola, I am told, is such that its wings visibly flex if you felt inclined to watch them out the window.
Beyond the net cage, the body of the plane has been hollowed out and is lined with a dozen experiments, including a squid-like gripper for capturing space debris, someone playing Pac-Man while wearing an EEG helmet and breathing mask, and a scientist being pulled back and forth along a shuttle contraption while blindfolded. Everyone is tethered to a rail or the floor.
One scientist tells me the brain may work better in zero gravity because blood does not have to work against gravity to deliver oxygen. And each parabola does feel as if I’m entering a state of hyper-reality.
On landing, as I descend from the plane, I consciously feel the Earth’s pull for the first time. In total I’ve spent 11 minutes in weightlessness. It is a short but breathtaking glimpse of life beyond the confines of our home planet.