NASA: Kepler telescope finds another 715 planets

February 26, 2014 03:16 PM

UPDATED February 26, 2014 03:19 PM

More Videos

  • How much exercise do you need?

    If you turn on the TV, you're bound to see advertisements for a variety of exercise programs guaranteed to help you get in shape and improve your cardiovascular health. But how much exercise do you really need to be heart-healthy? And what type of exercise is best?