It was only yesterday that we reported the rumors that Natalie Portman had been offered the lead in Alfonso Cuaron's sci-fi survival movie Gravity, and that Gemma Arterton might be fighting off xenomorphs in Ridley Scott's Alien prequel, but both rumors seem to have been debunked already.

Of the two, the Arterton/Alien rumor was the more forcefully debunked, with a publicist for the actress telling MTV in no uncertain terms, "There's no truth to that." Portman's publicist is being a little more cagey, when it comes to the Gravity story, telling Techland, "A lot of the information is inaccurate. Everything is pretty much just rumored... We did not announce anything this morning in relation to Gravity." So, perhaps there's still hope there, if Warners can make it worth Portman's time...