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It lets users see instantly where in the skies the International Space Station is, using a Google Maps-based system (at the time of writing it is over the North Pacific, just south of Alaska, moving towards the western United States and Mexico). If a Space Shuttle was flying, iPhone owners could track that too. You can also use it to keep up to date with Constellation, the proposed Space Shuttle replacement. The Ares 1-X rocket, the first test rocket of the new mission, is expected to launch on 27 October. It also provides an Image of the Day – currently a pre-launch shot of Ares 1-X – and an Astronomy Picture of the Day, currently a series of beautiful images of galaxies called Galaxy Zoo.