2MASS 2MASS galaxy catalog adaptive optics Alvaro Orsi Andromeda Galaxy Arp 194 asteroid asteroids astronomical event ATLASGAL atomic clock aurora Betelgeuse Cassiopeia A Chandra telescope Chandra X-Ray Observatory climate clouds collision comets computer model computer models computer simulation conjunction Cosmic collision cosmology crater dark matter data manipulation Deep Impact Durham University dust dwarf galaxy Earthshine Echo satellite eclipse exploration extrasolar planet galactic plane galaxies galaxy galaxy cluster galaxy group Ganymede Hayden history hoax Hubble Space Telescope ice ice age impact infrared intermediate skill International Space Station interstellar gas Io Jupiter large-scale structure launch LCROSS leap second LRO lunar magnetic field magnetosphere manhattanhenge Mars Mars Reconnaissance Orbiter meteor meteorite microwave Milky Way Galaxy mission Moon MRO multiwavelength imagery NASA neutron star night sky Noctilucent Clouds observation optical orbit Orion partiview partiview tip planet red supergiant rock rocket satellite satellite launch solar eclipse Solar System space shuttle spiral arm star star formation Stars sunset Venus