By Brian Marder, Hollywood.com Staff

The highly anticipated, long-in-the-works, oft-delayed sci-fi thriller Gravity, starring Sandra Bullock and George Clooney, has been pushed back to 2013 by Warner Bros.

The film, in which a ""catastrophic event"" leaves astronauts Bullock and Clooney with nothing but each other and the darkness of space, was set for release fairly soon: Nov. 21, 2012. Alas, however, the Alfonso Cuaron-directed/co-written Gravity will not hit theaters until an unspecified date in 2013, with no concrete explanation given — which, of course, often tends to suggest that the movie wasn't quite ready for mass consumption.

Gravity has been in various states of production since 2010, when Angelina Jolie, Natalie Portman, Scarlett Johansson, Marion Cotillard and Blake Lively were all linked to the lead female role of Dr. Ryan Stone. Bullock fans will be sad to know that the Oscar-winning actress doesn't have anything else firmly lined up at the moment, though she was rumored late last year to star alongside Clint Eastwood in the drama Trouble with the Curve.

[Image: WENN]

More:

Sandra Bullock to Play Clint Eastwood's Daughter in 'Trouble with the Curve'?

Sandra Bullock in Talks for 'Gravity' Lead

'Gravity' Pulls In George Clooney

[THR]