Wilson da Silva has harboured the dream of space travel since childhood: 'I used to lie in Sydney on the front lawn looking up at the stars and imagine myself exploring the galaxy, and it just seemed like a thing that was very exciting and mind-expanding even as a 10-year-old.'
We're getting a lot closer, even though it has taken a lot longer than we originally thought.
'I imagine it's the same for Alan and for Victor and Alex—that we are all dreaming of the idea of actually experiencing being outside our own planet ... and to look at the world from the outside,' he says.
'It's not just the experience of zero gravity, which itself will be very exciting, but it's the actual idea of doing it, of being outside your planet, something that has only been done by something like 500 people in all of human history.
'That is an experience, and it changes people. A lot of people, particularly astronauts in the Apollo program who went very far, to the Moon, say that it substantially changed the people that they are, and we hope that we will get a little bit of that.'
As excited as da Silva and his fellow space travellers are, they may have to wait a while a while. Branson has been predicting for more than a decade that space tourism is imminent but there have been substantial delays. Da Silva, who bought his ticket back in 2004, and has already done some simulation training in preparation for space flight, is still waiting.
'I've been saying for a number of years now, "next year",' he laughs, 'and so far I've been accurate: it's always next year.'
Virgin Galactic is not the only company that is aiming to get a piece of the space tourism pie. There is now something of a tourism space race underway between Branson's company and two others—Blue Origin, funded by Jeff Bezos, the founder of Amazon, and XCOR, which is developing a space plane called Lynx that will carry just a pilot and a passenger.
Although some tourists have already headed into space, forking out millions of dollars for a seat on the Russian Soyuz capsule, the private companies that are now in the space tourism race are offering a much cheaper option. Instead of full orbit, travellers will simply have a sub-orbital experience. Jeff Foust, editor of US-based The Space Review, has been watching the developments closely.
'Unlike a satellite or the space station or something that is in orbit around the Earth, you simply go pretty much straight up to an altitude of about 100 kilometres or so, and then come right back down without going into orbit, so you only get to spend several minutes in space,' he says.
'You get a taste of the zero-gravity environment and a view of the black sky and a view of the Earth out the window and so on, but you only get that for a matter of minutes rather than hours or days or weeks like if you are in orbit.'
Despite the pared-back space experience, the technological hurdles remain great. In 2007 three engineers were killed in an explosion when a tank of nitrous oxide exploded during work on Virgin Galactic's propellant system. More recently, in 2014, a co-pilot was killed and another injured when the company's spacecraft disintegrated during a test, an accident that was later attributed to human error.
'Safety, yes, of course it does cross your mind,' da Silva says. 'But the very beginning of flying, something we do every day, began like this. It was very, very risky at the beginning of flight—in fact in the first years of the 1920s something like 25 per cent of pilots died every year.'
Da Silva likens the experience to other risk-taking pursuits like climbing Mount Everest. 'Having said that, going to space has a three per cent non-return rate in the sense of the number of people who have gone to space and haven't come back, whereas going to Mount Everest is 4.7 per cent, so I think even the odds are little bit better.'
Steven Freeland, a professor in international law at Western Sydney University with a particular interest in space law, says while the technology is moving at a rapid rate, there are still many hurdles to overcome before a fully fledged space tourism industry can become a reality—not just safety.
'There are lots of other regulatory issues and standards for safety and even ethical considerations that I really think will need to be sorted out before this can ever become an industry. And by "industry" we are talking here about the potential for this to become large numbers of paying passengers on a commercial basis rather than the odd person,' he says.
'We don't actually know where airspace ends and outer space begins ... and that is relevant from a legal viewpoint because the international framework for airspace is very, very different and predicated on totally different assumptions than the legal framework for outer space.'
Although Freeland believes we could still be a couple of decades away before we see a fully fledged commercial space tourism industry, Foust is more upbeat.
'I think realistically we are looking at flights carrying people within about the next two years. The question will be: will all three companies be ready to go in two years? It's possible that one or more of them may have a setback of some kind,' Foust says.
'To be clear, it has taken a lot longer than people expected for these vehicles to be developed, but we are now finally getting to the point where we are seeing real flight hardware flying all the way to the edge of space. So we're getting a lot closer, even though it has taken a lot longer than we originally thought.'
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