It takes the "right stuff" to withstand cosmic bursts of camera light and meteoric bombardments of questions, but Tim Peake is orbit-ready and passed the test of facing the massed media on Monday morning. As Britain's first official, government-backed astronaut, his selection for a mission in late 2015 marks a pivotal moment. Countries as far afield as Belgium, Mexico and Vietnam have already had people in space, but so far the only Brits to make it have either had to change nationality (and become American) or win a Russian competition (as in the case of Helen Sharman in 1991).
For decades, British governments regarded astronauts as a rather strange and pointless luxury - the weightless floating about irrelevant to life on the ground and the costs far too extravagant to contemplate. This attitude was memorably summed up by Kenneth Clarke in the last Conservative government in the 1980s. When asked if Britain would contribute to the European Space Agency's role in the International Space Station, he replied that he didn't want to pay to put a Frenchman in space.
Since then, quietly and modestly, British space labs and companies have grown to become market leaders in key technologies and their business is valued at £9bn a year. The sensors that bring you those amazing pictures of the Sun, the rocket motors steering spacecraft, the harpoons that may help clear up space junk - many are designed and built in Britain. There are hopes that the space sector will grow - eventually to support as many as 100,000 jobs - and the figurehead of this renewed British effort in space is a former helicopter pilot from Chichester.
Science Minister David Willetts regards the £16m to secure Tim Peake's ticket as money well spent.
While NASA wraps its astronauts in the rhetoric of fabled explorers - lots of "celestial destiny" and "bold endeavour" - the British take is far more mundane: the press release announcing Tim Peake's mission is mainly about British industry and jobs.
So when he dons his spacesuit, and checks the Union Flag's in place, there'll be a lot riding on his multi-layered shoulders.
I first met him when he was picked for the European Space Agency's astronaut corps back in 2009 - the start of a long road to orbit - and he appeared exactly how you expect astronauts to look: calm, measured, ready for anything.
He's got the straight spine of a military man and the sharp gaze that NSA selectors have always favoured, and he turns his head in even, steady moves, not unlike those chisel-jawed heroes of Thunderbirds.
On Monday morning, after his news conference, his cheeks were flushed in a way that reminded me of Prince Harry, and his manner has the same relaxed air.
"I'm clearly delighted with the decision. It's a true privilege to be assigned to a long-duration space mission," he told me.
I asked about the much-pushed angle that his mission is partly about trying to boost economic growth.
"There's also the inspiration part - the true human exploration in terms of what we are doing.
"We are pushing the boundaries every time an astronaut goes up; we learn new things about ourselves, about our bodies."
Then the really big questions: yes, he does play the guitar, not well, but did actually once play with the legendary Chris Hadfield, the most musically famous astronaut of them all.
Via Twitter, I was asked if Tim Peake would introduce his fellow astronauts to the delights of a Full English Breakfast.
"I get to choose some of the European food that comes up with me, so a Full English breakfast might be top of the list."
So in November 2015, at the desert launch complex at Baikonur that saw Yuri Gargarin blaze a trail into orbit, Tim Peake will climb into the top of a Soyuz rocket.
The countdown will be in Russian. Tim Peake's training will make him comfortable with the language. And then the first jolt of launch will kick in.
Down below him, a blast of flame will send a wall of heat across the scrubby dunes towards the viewing stands and camera positions: this will make compulsive viewing in homes and schools across Britain.
Tim Peake will be given a vigorous shaking - "a moment nothing can prepare you for", he told me - as the rocket motors accelerate him into space, and a place in the history books.