Astronomy Picture of the Day . ... Earth is the only planet in the Solar System where the present surface temperature and pressure allow the three forms of water, solid (ice), liquid (ocean), and gas (water vapor condensing in clouds) to exist simultaneously. ... M83: A Barred Spiral Galaxy . ... M83 is a member of the Centaurus group of galaxies, a nearby group dominated by the massive galaxy Centaurus A. It takes light about 15 million years to reach us from M83. ... Bright Comet SOHO . ...