THR.com reports that both Scarlett Johansson and Blake Lively are interested in Alfonso Curaon’s upcoming film, Gravity, to which Robert Downey, Jr. is already attached.  The movie’s plot revolves around astronauts repairing the Hubble
telescope who are hit with an avalanche of satellite junk. In a plot
akin to “Cast Away,” the surviving astronaut must fight her way back to
Earth, where she hopes to reunite with her daughter.
  Although Downey is on board, the role of the female astronaut takes center stage in the movie.  Angelina Jolie was previously in talks, until negotiations broke down, reportedly over money.  marion Cotillard also tested for the role. 

Lively, currently the star of Gossip Girl, will be seen in both The Town and The Green Lantern.  Johansson could be making multiple future appearances as the Black Widow, with a role in The Avengers confirmed, perhaps for the inevitable Iron Man 3 (provided Marvel doesn’t cheap out) and also a rumored Nick Fury film (that last one is according to IMDB).  She also has Lunatic at Large in development.