Virgin Galactic 01 flight LIVE: Countdown until the airline's first commercial space flight

Virgin Galactic customers who have splashed out hundreds of thousands of dollars on a trip to space are finally set to be rewarded.

The firm, founded by British billionaire Sir Richard Branson, has confirmed it will perform its first commercial flight, 'Galactic 01', at the end of June, with a target flight date of Thursday June 29.

But who are the passengers on board the Virgin Galactic flight 'Galactic 01'?

Col. Walter Villadei

Col. Walter Villadei is a senior member of the Italian Air Froce, who will be using his experience to prepare for a future trek to the International Space Station.

Pantaleone Carlucci

Pantaleone Carlucci - a pilot and technical engineer from the National Research Council of Italy - will be conducting tests to determine human performance metrics during the flight to space.

Lt. Col. Angelo Landolfi

Lt. Col. Angelo Landolfi will also be conducting tests, however these will be in the field of cognitive performance in microgravity and study liquid-solid mixing.

Colin Bennett

The final of the four crew members is Colin Bennett, an astronaut instructor at Virgin Galactic, who has the all important task - ensuring what the quality of the experience is like travelling aboard the VSS Unity.

Bennett is also a lead astronaut instructor responsible for training and preparing the passengers.

Here's what you need to know:

What is Virgin Galactic?

Virgin Galactic is Richard Branson's commercial spaceflight company, which has been in the works since 2009.

The first flight, Galactic 01, launches at 4pm UK time on June 29, but without paying customers onboard.

It will instead carry three crewmembers of the Italian Air Force and National Research Council of Italy with one astronaut instructor from Virgin Galactic.

If successful, Galactic 01 could pave the way to tourists going to space on other Galactic flights later this year.

How much are Virgin Galactic tickets?

When they eventually can, a ticket for tourists to have the space experience will cost $450,000.

The organizers have said that this is a price people are willing to pay, and 'demand is high', according to the Virgin Galactic website, with several hundred customers already lined up.

How much does it cost to build the Virgin Galactic spacecraft?

According to research by New Space Economy, each flight will run up operational costs of $586,000, which includes the cost of running the motors, and customers' insurance.

To build the aircraft - of which there are currently three - it is expected that each costs roughly $35 million.

This means meaning one aircraft would need just 17 flights to become profitable, while they are built to last a decade, and the company hopes to end up flying each 50 times every year.

When is the first Galactic flight for tourists?

After Galactic 01's scientific mission at the end of June, the first flight with tourists is scheduled for August.

Galactic 02 has not had a specific date marked yet, but is due to take place early in the month.

From then on, flights are expected to run once a month according to the company's website, although they hope to expand their flight schedule within the first year.

What happens on board?

Galactic flights should last 90 minutes, beginning with a launch from 9.4 miles (15km) above Earth off a carrier plane.

That is already higher than typical commercial planes will fly at, which is only up to eight miles in altitude.

The aircraft and crew will then ascend to 50 miles (80km) over our planet, a suborbital altitude, meaning that they will reach the edge of space without actually going into orbit.

Once the spaceplane reaches the edge of space, it will hover in place for five minutes to let passengers experience zero gravity, and the fantastic views of both space and Earth from the array of windows in the roof and sides of the aircraft.