Bass, of the boy band 'N Sync, has been given informal word that he is physically fit enough to take a seat on a Russian rocket flight to the International Space Station.
The news comes just two weeks after he had a minor heart operation to rectify an irregular heartbeat.
He is now expected to start flight training at the cosmonaut centre in Russia's Star City on Monday, 3 June, which would last for five or six months.
"He's in top physical condition, top mental condition," according to David Krieff, a Hollywood producer who is arranging financial backing.
Bass's adventure will be followed on a series of US television specials.
Mr Krieff said Bass would be officially certified fit at "some sort of ceremony" on Wednesday after completing a series of physical and medical tests following the end of 'N Sync's latest tour.
If he comes through the flight training, he will be a contender for a seat on a re-supply mission that would last seven or eight days.
Ambition
Bass, 23, would become the youngest person ever to go into space, Mr Krieff said.
He has held the ambition since childhood, when he went to a space camp.
If successful, he could follow in the footsteps of Dennis Tito and Mark Shuttleworth, the world's first space tourists, who reportedly paid $20m (£14m) each for their trips to the international space station.
Mr Krieff said his company, Destiny Productions, was arranging corporate sponsorship as well as the TV deal.
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