For decades space travel was restricted to the fortunate few - astronauts who got their chance, if they were lucky, after years of training.
Today there is a new kind of space traveller - the tourist. And within a couple of years, these ordinary travellers could be making weekly voyages to the edge of space.
Hoping to run these regular civilian space flights is Virgin Galactic, which is aiming to ferry people into sub-orbit from as early as the end of 2013.
Virgin Galactic is not alone; US firms SpaceX and Bigelow Aerospace have announced a partnership to take tourists to Bigelow’s BA330 inflatable space stations using SpaceX’s Dragon reusable spacecraft and the, currently proof-of-concept, Skylon space plane is expected to be capable of carrying humans into orbit before 2020.
Mark Hempsell, future programmes director with Reaction Engines Ltd (REL), the UK company which designed Skylon, said that until recently the aerospace industry believed space tourism to be a long way off.
“We would have said space tourism will happen eventually, but it will be one of the last applications of space,” said Hempsell.
But space tourist pioneers like Richard Garriott, the creator of the Ultima video game series who paid $30m for a trip to the International Space Station inside a Soyuz capsule in 2008, have shown there’s a market for space flight among the super rich.
Instead of space tourism being a late application of space travel technology it’s one of the first, said Hempsell. “There has been a dawning realisation that there are people who are prepared to spend hundreds of thousands to millions to get into space - and that creates a market.”
On the back of that market Virgin Galactic have sold more than 500 tickets for flights on board its SpaceShipTwo craft. George Whitesides, CEO of Virgin Galactic, told TechRepublic: “For 50 years space has been the province of these super-elite professionals. We’re cracking it open so we fly the same number of people in the first couple of years as have ever been to space during the past 50 years.”
But there is one thorny issue, the price. A trip on board Virgin Galactic may buy you some six minutes of weightlessness and a view of the curvature of the earth, but it will cost you $200,000.
Whitesides said that a sub-orbital flight with Virgin Galactic “may stay around $200,000 for a while” but will come down over time.
Nevertheless the spread of space tourism is unlikely to stop at sub-orbital level - some 60 miles above the earth - with Hempsell predicting a market for journeys into orbit or beyond - albeit at a higher price tag.
“On our system fully orbital flights could work for half a million a seat,” he said, adding he could see it happening within 10 years.
He is reasonably confident that Skylon, which is initially being designed with non-human payloads in mind, will carry people into orbit as part of the vehicle’s test flight programme, expected to begin some time around 2019.
“I do think that we will see the first human flights within this decade, assuming that somebody develops a cabin to go inside the bay,” he said. “The cabin is not a cheap system to develop, it’s billions in its own right, but it does look like it can be made to pay.”
Skylon, still at a proof-of-concept stage, has been designed to take off from a runway, fly into space and then land back on a runway, all without the need for a separate launcher.
It will use a combined jet and rocket engines called Sabre, which will burn oxygen from the air until Skylon reaches a speed of Mach 5.5 and an altitude of 25km, at which point it will change to rocket engine mode and burn its store of liquid oxygen to accelerate to a speed of Mach 25 and complete its climb into orbit.
Skylon’s cost advantage will come from being reusable. Rockets used to carry payloads into orbit today are not designed to be reused, which adds to the cost of transporting people, equipment and spacecraft. REL’s Hempsell estimates that the cost of carrying a non-human payload into orbit using the space plane will be some 50 times cheaper than current launch costs.
Skylon is being designed as an autonomous vehicle, relying on flight control systems to get itself to and from orbit and deliver its payload. Even if a human pilot were put in charge of a Skylon it would be necessary for the onboard computers to control the plane for much of the flight because it would be travelling too fast for a human, with their relatively slow reaction times, to handle it.
REL’s Sabre engine should, according to Hempsell, be ready for use in a test flight in six years.
Also pushing the space tourism industry forward is vintage technology like the Soyuz spacecraft, originally designed in Soviet Russia in the 1960s. Soyuz is a mature technology whose development costs were largely absorbed by government decades ago. The craft’s proven track record makes it a good choice for companies like Space Adventures looking to establish an economically viable space tourism operation.
As a result, trips further into the cosmos are already available to hardy travellers with exceptionally deep pockets. Space Adventures has reportedly sold one ticket for a trip around the moon inside a Russian Soyuz craft for a cool $150m.
Intercontinental travel on the edge of space
Even if the appeal of space tourism fizzles out in the face of high costs, planes capable of flying at super or even hypersonic speeds in the upper atmosphere could dramatically reduce the time it takes to travel between continents.
Virgin Galactic’s Whitesides said the company is studying such alternative uses for technologies used in SpaceShipTwo, which can reach speeds of Mach 3.5 using its rocket engines.
“One of the things that we’re excited about at Virgin is thinking about how these technologies in this vehicle could be applied to point to point travel at some point in the future,” said Whitesides.
“We’ve been stuck at roughly the same speed in terms of intercontinental air travel for 40 years. Our hope is that we may be able to apply some of these technologies to allow us to break out of that plateau we’ve been in for so long.”
The UK’s REL is involved in a EC-funded project called LAPCAT to research the technologies needed for a plane that could fly at Mach 5 for 20,000km. The project is examining what technologies would be needed to build a plane that could travel from Brussels in Belgium to Sydney in Australia in two to four hours.
However, Hempsell said that developing such a plane poses a greater challenge than building Skylon.
“It’s more difficult to do and much longer term,” he said.
“With Skylon we stay at Mach 5 for two minutes, and the outside skin at those altitudes rises to close to 1,000C. To do it for four hours on the way to Sydney is going to require something a little more. Even if the outside materials could survive the temperature the passengers won’t.
“There’s ideas about how you might solve these challenges but it’s a considerably tougher prospect.”
The future of civilian space flight
While hypersonic jet setting may be a long way off and space tourism may remain the preserve of the wealthy for the forseeable future, Virgin Galactic’s Whitesides remains confident that space travel is going to become increasingly accessible.
He said: “What’s clear is that space travel is ripe for revolution and for a radical transformation of the number of people who have access to space.”