To infinity and beyond: Britain’s first space tourists could travel into the galaxy by the end of 2013.

The shape of travel to come will be unveiled by Sir Richard Branson today when he gives an update on his space tourism plans. Sir Richard is at the Farnborough Air Show to provide the latest news on his Virgin Galactic company.

The world's first commercial spaceline, Virgin Galactic will see tourists going up into space via first a carrier aircraft - WhiteKnightTwo - and then a sub-orbital space vehicle, SpaceShipTwo (SS2).

Virgin Galactic chief executive and president George Whitesides has said the project is "on course for powered flight by the end of 2012".

Arriving at Farnborough today, Mr Whitesides said it was hoped the first passengers would be able to go up into space towards the end of next year.

He went on: "We hope to run flights on a weekly basis to start with.Passengers will go around 60 miles up into space and they will be able to float around the cabin due to weightlessness."

Around 500 people have put their names down for the 200,000 US dollar (£130,000) trips, which will last, from take-off to landing, for about two hours.

Mr Whitesides, who formerly worked at space agency Nasa, said the first 500 space tourists should be able to be accommodated by the end of 2014.

Various celebrities such as Hollywood stars Tom Hanks, Brad Pitt and Angelina Jolie have expressed interest in becoming space tourists in a project in which passengers will attain heights of around 60 miles (97km) and experience weightlessness.

WhiteKnightTwo has already completed around 80 test flights, while American aviation authority the FAA has granted the project an experimental launch permit.

A full-scale replica of SS2 is on display at the Farnborough show in Hampshire, which runs until Sunday.

SS2 can take six passengers and two pilots. With WhiteKnightTwo, it will take off from a spaceport in New Mexico, USA, with SS2 being released at about 50,000ft (15,240m) to go into space.

After re-entry, SS2 will effectively become a glider and will land back at the New Mexico base.

Virgin Galactic is already building a second SS2 in the hope that demand for out-of-this-world travel will increase.

A number of the space tourists posed for pictures beside the SS2 replica. They included Scottish care home owner and “Secret Millionaire” Tony Banks, who posted on Twitter: “Off to Farnborough air show with Virgin Galactic crew today. Future space travellers!!! What a blast! Lol”

Irish businessman and author Bill Cullen, 70, was the first to sign up for a trip into space, paying his 200,000 dollars in 2004.

Accompanied by his partner, Jackie Lavin, he said today: "I wanted to be the first Irishman in space and I'm really looking forward to it. I've been interested in space ever since I followed comic hero Dan Dare when I was a kid."

Another space tourist at Farnborough today was businessman Grant Roberts, 36, formerly from East Sussex but now based in Dubai.

He was with his father, Michael, 65, and his grandfather Frank Roberts, 90, who was an RAF pilot who flew on missions over Germany in the Second World War.

"I was inspired by the exploits of my grandfather, as was my father," said Grant Roberts, who paid for his space trip in 2007.

He went on: "I can't wait to go up. The whole family plans to travel out to New Mexico with me."