Sandra Bullock has her brother-in-law to thank for finding a real-life astronaut to serve as her consultant on new movie Gravity after striking up a conversation with the spacewoman's sibling.

The Oscar winner reveals they were at a winery before she started shooting Gravity when her sister's husband learned he was chatting to the brother of an actual astronaut, who was working at the International Space Station (Iss), so he took care of the introductions.

She tells U.S. talk show host Jay Leno, "My brother-in-law hooked me up with an astronaut... We went to a winery, the brother of the astronaut packages wine stuff and he says, 'My sister's in space.' My brother-in-law says, 'My sister-in-law is going to space (in the movie)', so then we started drinking and it was great!

"She was already up in the Iss. She was already up in space... so it was perfect because we were just starting to figure out how to really do the weightlessness (for the film)... so I was able to call her, through the Iss, and ask, 'How does your body move in gravity versus land?' and all these really interesting pieces came to us at a time that we were just working on them."

Bullock, who portrays a medical engineer on a space shuttle mission gone wrong, had originally been forced to overcome her fear of flying to shoot her scenes strapped into a special airplane, nicknamed the Vomit Comet, to replicate the feeling of weightlessness, but director Alfonso Cuaron ended up scrapping the plan due to logistical issues. They instead filmed the space scenes using an elaborate set in London to simulate the out-of-this-world environment.