To honor NASA's discoveries, the USPS is debuting new stamps today with images from outer space. The "Views of Our Planets" series will get new images of Mercury, Venus, Mars, Jupiter, Saturn, Uranus, Neptune and the iconic "blue marble" view of Earth. Thanks to the New Horizons mission to Pluto, there's a special set of two stamps with a snapshot from July's flyby and the spacecraft itself. The eight new planet stamps are available at post offices and online, but the Pluto stamps will be sold only on the web. If you're looking to add a few to your collection, the entire set is available starting today.