Rocket plane SpaceShipOne is to attempt a second spaceflight on Monday in a bid to clinch the $10m Ansari X-Prize.
The craft landed safely after an unexpected roll during the flight
Judges officially confirmed that pilot Mike Melvill took the craft to 103km (64 miles) on Wednesday's first flight.
There was concern that its second attempt could be delayed after the spaceship rolled unexpectedly and perilously during its first attempt.
Under the X-Prize rules, contenders must pass the 100km mark twice inside two weeks in the same craft.
On both occasions, craft need to fly with a pilot and at least the ballast equivalent of two other people.
The Ansari X-Prize was set up to galvanise the commercial spaceflight business. It is hoped the competition will kick-start space tourism with ordinary people buying tickets to go on short, sub-orbital trips.
Rock and roll
The second flight will take place on the anniversary of Sputnik's 1957 launch. It is also the start of the United Nation's World Space Week.
After Wednesday's dramatic trip, Mr Melvill said SpaceShipOne had surprised him with its "little victory roll" as it raced up through the top of the atmosphere.
It is not clear whether Mr Melvill will pilot the second flight
He had shut down the engines 11 seconds prematurely as a result, but only after he knew the craft would pass 100km.
Mr Melvill and Burt Rutan, the aviation pioneer behind the team and the rocket plane, downplayed the events saying the corkscrew ascent had also occurred during flight simulations.
The craft rolled several times as it travelled nearly three times the speed of sound, but Mr Melvill said it could have been caused by him accidentally stepping on a pedal during the boost stage.
It is not known whether the highly experienced Mr Melvill, who also piloted SpaceShipOne on its landmark test flight in June, would be the pilot on Monday.
Four test pilots have been trained to take the ship into space and back.
It was also unclear whether there would be any passengers on the craft for the flight which could claim the $10m prize.
Mr Rutan told BBC News Online in August that he would be one of SpaceShipOne's first passengers.
Among the cargo on Wednesday's flight was video and other monitoring equipment required for X-Prize altitude verification, as well as the ashes of Mr Rutan's mother.
The craft rolled about two dozen times
Mr Melvill also took his wife's wedding ring which had only left her finger once in 43 years of marriage.
Also on board was a teddy bear from the UK called Terrence which has travelled around the world on a mission to raise cash for the Great North Air Ambulance.
SpaceShipOne's second attempt takes place at California's Mojave Airport at 0700PDT (1400GMT).