On a mission to fix a leaky valve, I'm pulling myself rung by rung along the International Space Station. The Earth is shimmering below in a way I've only seen in pictures, and if I turn my head, I can see the outer reaches of the station, and beyond them, endless space.

I'm holding on for dear life, but it's only instinct — my feet are safely on the ground of the Earthlight booth at the Melbourne Convention Centre.

See also: A look back at life on the Space Station over the past 15 years

Created by Melbourne-based studio Opaque Media Group (OMG), with advice from NASA, the Earthlight virtual reality experience let me briefly space walk on Sunday from the comfort of the gaming convention, PAX Australia.

"Out of the 7 billion people currently alive, and out of the billions of people who came before us, only 536 people have been to space," Norman Wang, project lead on Earthlight, told me. "We want people to be able to experience what it's like to be an astronaut and what it's like to be in space."

Pulling Earthlight's HTC Vive VR headset over my eyes, I certainly came the closest I've ever been to microgravity, and I want to go back as soon as possible.

The Earthlight VR headset and hand controllers. Image: George Voulgaropoulos

During the 10 minute session, Valve controllers tracked my movements so my arms were mirrored in the virtual world — it was disconcerting to see my hands gesturing, encased in the white gloves of a spacesuit. A button on the controller let me grip in order to pull myself out of a bolthole and onto the exterior of the International Space Station (ISS). It also took a moment to get used to my limited peripheral vision, heavily reduced by the bulky space helmet obscuring my vision in virtual reality. This hindrance is true to life, Wang later explained, as standard space suits don't let astronauts look down or around easily. Travelling hand over hand along the outside of the space ship, I felt some of the slowness of moving in a weightless environment and the care that astronauts must take with every gesture.

When the valve eventually burst, sending me off spinning into space à la Sandra Bullock in Gravity, the sense of vertigo was genuine. If it wasn't for the raucous cheers from the war gaming booth next door, bringing me crashing back down to Earth, it might have taken awhile to collect myself.

The Earthlight VR first-person experience. Image: George Voulgaropoulos

A vastly complicated digital experience to construct, OMG had to work not only on creating accurate visuals of the ISS with VR developer tools, Unreal Engine 4 and Steam VR, but also on the authenticity of the movements of the astronaut. Wang said the team has consulted with NASA to make sure they create the most true-to-life experiences possible.

"Our key collaboration with the Jet Propulsion Laboratory was facilitated through some of our work with Microsoft," he said. "JPL has had a copy of Earthlight for sometime now and provided us with feedback as to the design and interface."

Wang said they're still developing Earthlight's content, including a sequence that would mirror that of how an astronaut trains for space travel, as well as some of the smaller details. "We want to use the haptic feedback and the vibration of the handsets to, for example, let you feel the handrail when you're not looking at it and can't find it because of the helmet's size," he said.

The studio has also talked to NASA about using the program for their own staff, Wang added. "They do have their internal systems for training ... but if you're trying to familiarise yourself with the layout of the station, the placement of handles, there is probably a space for something like this," Wang explained. Unfortunately, he hadn't heard whether any NASA employees who have actually been to space have tried Earthlight.

The goal is to make an extended Earthlight package available to the public in early 2016 on HTC Vive, Oculus Rift and PlayStation VR. "I've never met a single person who didn't want to go to space," Wang said. "I think that's going to be true for most people."