This year provided plenty of cosmic eye-openers for astronomers and casual stargazers alike. Neighborhood planets such as Mercury and Jupiter received makeovers in both a scientific and literal sense. The discovery of water on the moon and Mars provided clues to the past, not to mention hints for the future of space exploration. And a class of newly-detected “Super-Earth” planets around alien stars may ultimately prove more habitable than Earth. Here are the stories that stood out:
Read more SPACE.com — 9 Astronomy Milestones in 2009.