The first official British astronaut is expected to be announced by the European Space Agency (Esa), MoD sources have told BBC News.
Timothy Peake, a 37-year-old test pilot in the Army Air Corps, has been accepted into the European Space Agency's (Esa) Astronaut Corps.
Esa is expected to name a 37-year-old Apache pilot from the Army Air Corps as one of six new recruits.
The spaceman, who hails from Chichester, was unveiled at a ceremony in Paris, along with five other new colleagues from across Europe.
The candidates will be presented to the public at a special ceremony in Paris.
The other recruits to emerge from Esa's latest trawl for new astronauts includes the first woman astronaut.
The appointment is somewhat surprising because Britain does not contribute to Esa's human spaceflight programme.
There are two Italians, a Frenchman, a German, and a Dane.
Its preference has always been to fund the robotic exploration of space.
But it is the appointment of a Briton which will surprise many.
Those British-born people who have gone into orbit have done so privately or they have taken out US citizenship to fly with Nasa.
Successive British governments have considered human spaceflight an expensive distraction, preferring to fund robotic exploration Instead.
This policy has made it extremely difficult for British-born individuals to get into orbit.
The first Briton in space was Sheffield-born chemist Helen Sharman. She had to secure private funding to fly to the Mir space station on a Russian Soyuz craft in 1991.
The first Briton in space was Sheffield-born chemist Helen Sharman. She had to secure private funding to fly to the Mir space station on a Russian Soyuz craft in 1991.
Three British-born astronauts have flown into space under an American flag: Michael Foale, Piers Sellers and Nicholas Patrick.
Three British-born astronauts have flown into space under an American flag: Michael Foale, Piers Sellers and Nicholas Patrick.
Esa says its new astronauts were selected solely on their ability to do the job.
But the European Space agency says its new astronauts were judged solely on their ability to do the job, not on national government policy.
The new recruits were selected from more than 8,000 applications and have been described as young and extremely capable individuals.
Timothy Peake and his new colleagues will now train to fly to the space station and with renewed interest in the Moon, they could conceivably also get to walk on the lunar surface one day.
The new astronauts are likely to get to fly on the space station
The astronauts will train to work on the space station and, depending on future developments, may even get to go to the Moon.
It is possible they could also pilot the first manned European spaceship.
Esa is just about to initiate a study that will look at the feasibility of turning its robotic ATV space freighter into a crew transportation vehicle.
"We're looking for... additional European astronauts," Simonetta Di Pippo, Esa's director of human spaceflight, told BBC News at the weekend. She declined to discuss nationalities or names.
"These are young candidates. I must say I found a very high level of expertise and capability. We started with 8,400... so you can imagine how tough it was. I'm really proud of what I saw in the last few weeks."
This recruitment campaign is Esa's first astronaut selection since 1992. It currently has eight men in its astronaut corps - from Germany, France, Italy, Belgium, the Netherlands, and Sweden.
The Belgian Frank de Winne is about to assume command of the International Space Station - the first non-US, non-Russian to do so.
There will be an expectation also in Germany, France, and Italy that one of their nationals makes it through to the final selection. These are the Esa member-states that have committed most money to the space station programme, the agency having spent of the order of five billion euros on the project so far.
The UK on the other hand has chosen to ignore Esa's "optional" human spaceflight programme. One of the major consequences of this position is that it has also locked UK companies out of the lucrative contracts to build space station equipment.
Business opportunities
British firms will be looking to see whether there are now business possibilities for them on the back of a UK astronaut.
What is clear is that the flight prospects for all European astronauts are going to be limited in the coming years.
Because Esa does not currently have its own crew ship, it must rely on seats being made available in Russian and American vehicles. But with the US shuttle about to be retired and a replacement craft not due to come into service until perhaps 2015, the opportunities to go into orbit will be greatly reduced.
Europe is considering building its own crew transporter. Member states have approved a study that would assess how the robotic Automated Transfer Vehicle could be upgraded, first to bring cargo safely back to Earth and then, perhaps, humans.
But it would be the end of the next decade before such a vehicle became operational - if it were ever built.
However, if the project were approved, it is conceivable that Wednesday's new recruits would be among the first to fly in the ship.
Certainly, Di Pippo believes Europe should press ahead with the venture.
"My slogan is that in a global endeavour 'we need autonomy for co-operation'," she told BBC News.
"So by increasing the autonomy of Europe, we will increase the robustness of the partnership."
