Download: WorldWide Telescope Spring Release
WorldWide Telescope is an application designed to turn your PC into a "virtual telescope" by stitching together terabytes (soon to be petabytes) of high-resolution images of the universe. Massive amounts of data are generated by the various scientific and research facilities and WorldWide Telescope brings the catalog of that data together for anyone to access using the power of the Internet. This new application is particularly exciting for me being someone really heavy into astronomy. You can also use WorldWide Telescope and connect an ASCOM-capable Telescope to your PC to watch the night sky.
WorldWide Telescope lets me connect to Communities, access Collections of celestial objects such as the Solar System or Constellations, or take Guides Tours.