In May 2013, Sigourney Weaver graced the American Ballet Theatre Spring Gala wearing a bob that had a nice texture to it, thanks to the subtle layering. The Alien and Avatar star is one of several over-50 celebs who have chosen the bob as their signature haircut, and we think she always looks great wearing her go-to style. Now a septuagenarian, Sigourney continues to amaze us with her energy playing kick-ass roles. Her secret? "It's important to grow old gracefully," she said to Times Live. "I am here to stay. I take care of myself and I don't have any big beauty secrets, but I do have the discipline to stay fit and have good health until I am very old."