CREATING A WORLD

Italian director and festival jury head Bernardo Bertolucci, at the opening ceremony which featured stars and models parading into the festival palace on the Lido island to the sound of a band and screaming fans, said: "Perhaps cinema cannot change the world, but we know that cinema can create a world."

Clooney, asked whether it had been lonely working on a set where often he or Bullock were seen alone, said they had to stifle their natural reactions in order to portray their characters, and they sometimes felt the peril was real.

"There was a giant piece of machinery I think they used to build cars with that would come flying towards you at 40 mph," Clooney said.

"I think the great challenge we found, as opposed to feeling alone in space, was to not react when this 4,000-lb machine came flying at you and would stop this close."

Bullock's character Stone, who left behind a job as a hospital lab doctor on Earth, appears alone on-screen for much of the film.

The "hell of a ride" she takes on the shuttle Explorer, complete with corpses, fireballs and faulty re-entry parachutes, follows the long drives she used to take after the death of her daughter was communicated to her in a telephone call.

"I was driving when I got the call, so now I just ... drive," Stone tells Kowalsky as the two traverse the galaxy.

Floating in space is an obvious metaphor for a character losing her way on Earth, co-writer and director Cuaron said.

"You have a character who is gripped in her own inertia: on one hand she has life, she has planet Earth, human connections and on the other side she's drifting," he said.

Clooney and Bullock open 70th Venice Film Festival	Jury members pose during photocall