Ever since Yuri Gagarin strapped himself in and blasted off on a Vostok rocket in 1961 to bravely go where no man had gone before, millions have dreamed of following in his exhaust trail.

But few have had the opportunity. Just 536 to be precise.

Enterprising startups such as Virgin Galactic, Blue Origin and SpaceX are bringing the idea of commercial space travel tantalisingly close.

But since Nasa ended its manned space programme in 2011, the dream of becoming an astronaut has largely been the preserve of the uber-rich. Just look at the founders of those three companies: Jeff Bezos, Sir Richard Branson, Elon Musk.

While being a billionaire is not a prerequisite for wannabe astronauts, it’s fair to say that space flight it likely to remain an elite activity for some time. A sub-orbital flight with Virgin Galactic will likely cost around £200,000, for example.

But one US company is attempting to change that with a five-year training programme for those who think they have what it takes to hurtle into orbit.

SpaceX Dragon heads back to earth after ISS mission Show all 15 1 /15 SpaceX Dragon heads back to earth after ISS mission SpaceX Dragon heads back to earth after ISS mission Space X Dragon departs from the International Space Station and heads for earth AP SpaceX Dragon heads back to earth after ISS mission Space X Dragon undocks from the International Space Station NASA SpaceX Dragon heads back to earth after ISS mission SpaceX Crew Dragon is pictured about 20 meters (66 feet) away from the International Space Station Nasa/AP SpaceX Dragon heads back to earth after ISS mission A SpaceX Falcon 9 rocket, carrying the Crew Dragon spacecraft, lifts off on March 2 2019 Reuters SpaceX Dragon heads back to earth after ISS mission Astronauts aboard the Space Station preparing to open hatchet to the SpaceX Dragon capsule carrying a instrumented dummy after it successfully docked with Space Station Nasa TV/EPA SpaceX Dragon heads back to earth after ISS mission A dummy(L) named Ripley onboard a SpaceX Falcon 9 rocket with the company's Crew Dragon spacecraft onboard after the opening of the hatch during the Demo-1 missioN Nasa TV/AP SpaceX Dragon heads back to earth after ISS mission The SpaceX team watches as the SpaceX Crew Dragon docks with the International Space Station Nasa/AP SpaceX Dragon heads back to earth after ISS mission SpaceX Falcon 9 rocket docked with the International Space Station during the Demo-1 mission Nasa/AFP/Getty SpaceX Dragon heads back to earth after ISS mission A SpaceX Falcon 9 rocket, carrying the Crew Dragon spacecraft Reuters SpaceX Dragon heads back to earth after ISS mission Astronaut David Saint-Jacques taking a look inside the SpaceX Dragon capsule carrying a instrumented dummy Nasa TV/EPA SpaceX Dragon heads back to earth after ISS mission A SpaceX Falcon 9 rocket, carrying the Crew Dragon spacecraft lifts off on an uncrewed test flight Reuters SpaceX Dragon heads back to earth after ISS mission A SpaceX Falcon 9 rocket, carrying the Crew Dragon spacecraft, lifts off on an uncrewed test flight Reuters SpaceX Dragon heads back to earth after ISS mission A SpaceX Falcon 9 rocket with a demo Crew Dragon spacecraft on an uncrewed test flight AP SpaceX Dragon heads back to earth after ISS mission SpaceX's new crew capsule approaches just before docking Nasa TV/AP SpaceX Dragon heads back to earth after ISS mission Astronaut Eric Boe, assistant to the chief of the astronaut office for commercial crew, left, and Norm Knight, deputy director of flight operations at Nasa's Johnson Space Center watch the launch of a SpaceX Falcon 9 rocket carrying the company's Crew Dragon spacecraft Nasa/AP

AdvancingX is running a global Career Astronauts competition which is free to enter. Successful candidates will be put through their paces in a range of tasks designed to create the perfect space team. Hundreds of candidates will be whittled down over five years to just 40. Eventually, four lucky winners will get the chance to fly into space.

Dr Mindy Howard, one of the trainers on the course, knows a thing or two about the demands of space travel, having made the grade as one of NASA’s ‘Highly Qualified Astronaut Candidates’.

While undergoing her own astronaut training she flew in parabolic flights which ascend at a steep angle before reducing altitude to give passengers a weightless experience. She’s also tested herself in an high-g centrifuge which spins you round to mimic the intense physical pressures of a rocket launch.

Scuba diving with submersible craft is part of the training (AdvancingX)

While Dr Howard has not yet made it into space she is now passing on the skills she has learnt to train the next generation of potential astronauts.

Dr Howard will teach candidates on the Career Astronaut programme about the mental toughness needed to travel into space, using techniques developed for her company Inner Space Training.

AdvancingX will also take the astronauts-to-be Scuba diving, using submersible craft to prepare them for carrying out tasks in a low-gravity environment.

AdvancingX’s chief executive Dr Eduardo Diaz says he plans to use biosensor technology to mitigate health risks of space travel and increase the success of teams in a “new era” of the career astronaut.

(Mindy Howard (Mindy Howard)

Dr Diaz wants to select those who can work well enough in a team to one day occupy a lunar base, or even one further afield.

“The employment opportunities are enormous,” he says.

“Imagine an entirely new society that will need every kind of human resource necessary to survive.

“There's a need for farmers, medical personnel, and mechanical engineers just to name a few.”

Candidates will even construct habitats in Icelandic lava tunnels which aim to mimic the desolate environment one might find on the moon or a distant planet.

NASA at 60: Amazing photos of space exploration released from archives Show all 21 1 /21 NASA at 60: Amazing photos of space exploration released from archives NASA at 60: Amazing photos of space exploration released from archives Robert McCall’s mid-1970s prediction of NASA’s space shuttle building a modular space station is close to what finally happened, except that the real shuttles only flew one at a time. Courtesy of NASA NASA at 60: Amazing photos of space exploration released from archives Ed White photographed by Gemini 4 Commander Jim McDivitt. During the first of 66 orbits, they made an unsuccessful attempt to rendezvous with the spent upper stage of their Titan launch vehicle. On McDivitt’s advice, White waited one more orbit to recover from the effort of the failed rendezvous, and then exited the Gemini for his historic spacewalk on June 3, 1965. Courtesy of NASA NASA at 60: Amazing photos of space exploration released from archives Apollo 9 CM pilot Dave Scott emerges from the hatch, testing some of the spacesuit systems that will be used for lunar operations. The photo was taken from the hatch of the docked LM by Rusty Schweickart in March 1969. Courtesy of NASA NASA at 60: Amazing photos of space exploration released from archives Mothership “Balls Three” overflies an X-15 in 1961. Three operational X-15s were constructed and flown for 199 test flights between them, as they pushed at the “envelopes” of speed and altitude, and reached the very edges of space. Courtesy of NASA NASA at 60: Amazing photos of space exploration released from archives The Mercury Control Center (MCC) at Cape Canaveral supervised seven human spaceflights between May 1961 and March 1965, into the beginning of the Gemini era. Meanwhile the more advanced control complex in Houston was taking shape ahead of Apollo. Courtesy of NASA NASA at 60: Amazing photos of space exploration released from archives Technicians working at the base of Alan Shepard’s Mercury-Redstone 3 launch vehicle are swathed in vapour from vented excess oxidiser gas on May 5, 1961. Subsequent rockets could not be so closely approached when fueling. Courtesy of NASA NASA at 60: Amazing photos of space exploration released from archives The Rendezvous Docking Simulator at Langley prepared Gemini astronauts for the strange physics of orbital flight. Courtesy of NASA NASA at 60: Amazing photos of space exploration released from archives Ahead of Gemini 10, Commander John Young explains to the media how copilot Michael Collins will inspect the Agena Target Docking Vehicle during his spacewalk, 1966. Courtesy of NASA NASA at 60: Amazing photos of space exploration released from archives Navy divers prepare to retrieve the Gemini 6A crew on December 16, 1965. Green dye was released by spacecraft on splashdown, making it easier to spot from the air. Courtesy of NASA NASA at 60: Amazing photos of space exploration released from archives The U.S. geological Survey’s map of the area around Tycho Crater, famous as the site of a mysterious alien monolith in the 1968 science fiction film “2001: A Space Odyssey.” In real life, this chaotic and rugged terrain would have been too difficult for an Apollo mission to access. Courtesy of NASA NASA at 60: Amazing photos of space exploration released from archives Apollo 11 Command Module Pilot Michael Collins inspects NASA’s Lunar Receiving Laboratory at the Manned Spacecraft Center in Houston, where rock samples collected by Apollo were analysed. Nitrogen gas protected the rocks from accidental corrosion in Earth’s oxygen-rich atmosphere. Courtesy of NASA NASA at 60: Amazing photos of space exploration released from archives NASA scientists are confident that Buzz Aldrin’s boot prints from Apollo 11 are still as sharp and distinct today as when they were first stamped down in 1969, because the Moon has no air or rain to erode them. Courtesy of NASA NASA at 60: Amazing photos of space exploration released from archives NASA’s Anechoic Chambers are among the quietest places anywhere on earth. Walls absorb almost all stray echoes, whether sound or radio. This 1972 model of a shuttle, being tested for radio characteristics, has thruster pods on the wingtips. Courtesy of NASA NASA at 60: Amazing photos of space exploration released from archives Lightning strikes the launchpad of Space Shuttle Challenger on August 30, 1983 prior to STS-8, the first pre-dawn launch of the space shuttle program. Launchpads are surrounded by tall lightning towers and other conductive systems.These create a giant “Faraday Cage,” diverting the electric charge of strike well away from the spacecraft. Courtesy of NASA NASA at 60: Amazing photos of space exploration released from archives The ISS has been continuously occupied since November 2000. Its habitable volume is equivalent to a Boeing 747’s. An international crew of six people live and work while traveling at five miles (8 km) per second, orbiting Earth once every 90 minutes. This is the single most complex and ambitious engineering effort in history, even when compared to Apollo. Courtesy of NASA NASA at 60: Amazing photos of space exploration released from archives The Hypersonic Inflatable Aerodynamic Decelerator (HIAD) is a hybrid of parachute and balloon technology. A new generation of flexible heat shield materials could enable a huge shield to be deployed from a small storage canister just before a spaceraft hits the atmosphere of its target planet. In July 2012 a HIAD survived a trip through Earth’s atmosphere at 7,600 mph. Courtesy of NASA NASA at 60: Amazing photos of space exploration released from archives In April 2016, ocean scientists at NASA’s Goddard Space Flight Center in Maryland, analysing data from Landsat 8, found mysterious lines crisscrossing the vegetation in the shallow waters of the North Caspian Sea.The cause turned out to be ice gouging at the seafloor in winter, before melting in the spring, and leaving just these clues. Courtesy of NASA NASA at 60: Amazing photos of space exploration released from archives Curiosity made this self-portrait on August 5, 2015, by maneuvering the Mars Hand Lens Imager (MAHLI) camera on the end of a seven-foot-long robotic arm. Multiple overlapping frames were acquired, then digitally stitched together by image analysts at JPL. The arm moved into a new position for each frame but the camera always pointed toward a specific “vanishing point” to minimize parallax distortions. Courtesy of NASA NASA at 60: Amazing photos of space exploration released from archives Jupiter's moon Io is dwarfed by the planet it orbits, as seen by the Cassini spacecraft en route to Saturn. Cassini’s 13-year tour of the ringed planet changed the course of planetary exploration. Courtesy of NASA NASA at 60: Amazing photos of space exploration released from archives A technician prepares to unlatch a small door built into the guide vanes of the Transonic Wind Tunnel at Langley Research Center in 2010. The vanes prevent turbulent eddies from interfering with the tests. Courtesy of NASA NASA at 60: Amazing photos of space exploration released from archives Courtesy of NASA

Is it far-fetched to believe that commercial astronauts will land on the moon any time soon?

Elon Musk, the boss of SpaceX doesn't think so. His pioneering company recently docked a craft at the International Space Station. He plans a manned mission there as soon as July and lunar flights are firmly within his sights.

“We should have a base on the moon, like a permanently occupied human base on the moon, and then send people to Mars,” Mr Musk said at a recent press event.

Those who want to apply for AdvancingX’s programme need to take a 20-minute behavioural assessment online. Successful candidates will then be assessed through a number of tests designed to find the best team players.