Virgin Galactic's space invasion will move a step closer to reality today when its mothership WhiteKnightTwo (WK2) is rolled out of its custom-built hangar in California's Mojave Desert.

Virgin chief Sir Richard Branson and designer Burt Rutan will unveil the twin-fuselage craft amid an international media frenzy. WhiteKnightTwo has been designed to transport the passenger-carrying SpaceShipTwo (SS2) towards the edge of the atmosphere. The SS2 pilots will then fire up their rocket engine and blast off into space.

The first-ever public viewing of WK2 is expected to attract Arnold Schwarzenegger, the Governor of California, as well as other politicians, government regulators and space tourism customers.



How it all began

British entrepreneur Branson's space dream dates back to the 1990s when he registered the Virgin Galactic brand. He said the establishment of the company was a step towards one day making "the affordable exploration of space by human beings a real possibility".

"It was Stephen Hawking who first got me thinking about this issue when he explained clearly and concisely that mankind had no option but to get into space as quickly as possible and start doing things up there that we have been doing on planet Earth, but in a much more efficient manner," said Branson.

In 2005 Virgin Galactic President Will Whitehorn told the US' House Aviation Subcommittee: "Sir Richard Branson identified that new technologies in composite materials, rocketry and computing could easily lead to the development of safe, economical, reusable spacecraft in the future."

Aerospace designer Rutan has a long history of working with Virgin and was to play a fundamental role in Virgin Galactic's development. Rutan was planning to build a spaceship with Microsoft co-founder Paul Allen and, when informed of this, Branson said he would produce a commercial version if the venture succeeded. On June 21, 2004, Mike Melvill piloted Rutan's craft SpaceShipOne (SS1) on the first private manned spaceflight.

The following October SS1 won the $10 million (Dh37m) Ansari X Prize for the first non-government organisation to launch a reusable manned craft into space twice within two weeks.

A few days earlier Branson and Rutan had announced plans to take the next step after the success of SS1 and built the first commercial spacecraft. The aim was to enable anyone willing to pay the ticket price to travel into space. Virgin Galactic licensed the designs of SS1, signing a $21.5m deal with Allen for the use of the technology and developing a $100m investment plan to build up to five spaceships at Rutan's factory in Mohave.

Virgin Galactic began operations in 2005 and announced in December of that year that it had signed up its first 100 passengers. By early 2008 it had received more than $31m in deposits from prospective passengers. Among them were Ashish Thakkar, Director of Dubai's Kensington Real Estate.

Others planning to travel with Virgin Galactic include French designer Philippe Starck, physicist Stephen Hawking, Hollywood director Brian Singer and environmentalist James Lovelock, creator of the Gaia theory.



WhiteKnightTwo and SpaceShipTwo

WK2 is the world's largest all carbon composite aircraft and its wingspan is similar to that of a Boeing 757's. SS2 is 18.3m long and 2.3m wide. It has a wingspan of 8.2m and a tail height of 4.6m and can carry two pilots and six passengers. The passenger cabin is 3.7m long and 2.3m wide. Virgin Galactic compares SS2's dimensions to those of a Gulfstream business jet.



Where will the first departure take place?

The first test and commercial flights of WK2 and SS2 will leave from Mojave, which is also the home of Burt Rutan's company Scaled Composites, the birthplace of SpaceShipOne and the site where SpaceShipTwo is being built. Virgin Galactic will then establish its headquarters and launch its spaceflights from the world's first private spaceport, Spaceport America in New Mexico.

The base will be built into the landscape so it can be heated and cooled efficiently – it will be powered by solar panels and have environment-friendly heating, cooling and ventilation systems.



The journey

WK2 will take off like any jet aircraft and is intended to carry SS2, attached to the underside, to an altitude of 15,000m.The SS2 pilots will then ignite its hybrid rocket motor and climb into sub-orbital pace. The SS2 will accelerate vertically to three times the speed of sound in about 90 seconds and climb to more than 109,000m.

After the engine is shut down the wings will be moved into position in preparation for re-entry. During this time SS2 will reach its highest point, estimated at 109,700m – and the passengers and crew will experience weightlessness. The astronauts will then recline in their seats and feel a gravitational force of six G – a rollercoaster may accelerate you to three or four Gs for brief periods.

At G-forces above four people black out as it becomes harder for the heart to pump blood to the brain. To counteract this the spacecraft designs place astronauts in sitting positions in the direction of the motion to distribute G-forces. SS2 will use a technique known as feathering, which involves the wings rotating to slow the vehicle down, during its descent.

The SS2 will feather until it falls to an altitude of 2,100m at which point the pilots will reconfigure the wings from feather to glider mode. The craft will then glide to earth, landing back at the spaceport.

The participants will at this point qualify for their astronaut wings, having flown above the US's minimum requirement of 80km above the earth.



Is it safe?

Whitehorn told the House Aviation Subcommittee about Virgin Galactic's commitment to safety, referring to the Virgin Group's experience as an airline and train operator.

"Safety obviously is our first priority," he said. "Suffice it to say that we have considerable experience in issues regarding passenger carriage and unwavering commitment to safety." Virgin says that due to the unique technology developed by Rutan's Scaled Composites and now exclusively licensed to Virgin, the spacecraft design overcomes many of the safety and cost issues that had previously made space travel the preserve of a privileged few.

An example of unique technology in the design of SS2 is the hybrid rocket engine, which does not require the storage of explosive propellants. The risks are less as the air launch does not expose the passengers to the risks associated with rocket launches from the ground. And if the rocket fails to ignite SS2 can glide back for a safe landing.

Astronauts will have three days of mandatory pre-flight preparation, bonding and training at the spaceport and will have medical checks.



How to book tickets

Once SS2 is completed – it will be unveiled next year – the first 100 passengers will take their turn to be flown into space. These pioneers have each paid $200,000 for the two-and-a-half-hour journey.

Additional passengers who will fly in the first year of operations will pay between $100,000 and $175,000. A $20,000 deposit is required. If you would like to book tickets visit www.virgingalactic.com