Clooney, 55, and Bullock, 49, looked radiant together as they posed for pictures at the AMC Lincoln Square Theater in Manhattan.
Cuarón initially considered Angelia Jolie for the part and when she turned it down, he turned to Natalie Portman. Scarlett Johansson and Blake Lively were also reported to be under consideration for the role.
But after Portman nixed the role, Bullock stepped up. It was probably a godsend.
Her chemistry with Clooney in the movie is off the scale.
George Cooney, Sandra Bullock Lead Gravity Red Carpet
(click photos to enlarge!)
Photos by Michael Loccisano, Dave Kotinsky/Getty Images
Bullock plays rookie astronaut, Dr Ryan Stone; Clooney plays veteran space traveler Matt Kowalsky, who is on his last mission. They run into problems when a wrecked Russian satellite slams into their space shuttle, tearing it to pieces.
Both are caught in the middle of a space walk and are thrown out into space. They must desperately maneuver to link up with the international space station, or they are doomed.
Bullock, who wore a Giambattista Valli dress and Giuseppe Zanotti shoes, was joined on the red carpet by another stunner, Emma Watson, who also wore white.
Watson, 23, wore an off-the-shoulder dress, with her hair back. She topped off the cream and white J. Mendel mini-dress with a white clutch and white and gold metallic cut-out heels.
Katie Holmes also look chic in a sleeve-less mini-dress by Azzedine Alaia. Katie rounded out the skater dress with a pleated skirt, wearing nude Louboutin heels.
Katrina Bowden also went with a casual chic look wearing a black sleeve-less top and matching pants.
Check out the photos from the red carpet and be sure to follow TheImproper on Twitter for all the latest film and fashion news.