Word of the day: Glabrous\GLAY-brus\ adjective: smooth; especially : having a surface without hairs or projections.
NEW: Star Gazing Moon and Saturn The Moon and the planet Saturn huddle close together tonight. They rise in mid evening, with Saturn just below the Moon. Saturn looks like a bright golden star.
Saturn has more than three dozen moons of its own. The biggest is Titan. It has a thick atmosphere that's topped by a layer of smog. The chemistry of Titan's atmosphere may resemble that of the very early Earth. That makes it a good laboratory for studying our own planet's history -- and leads to speculation that life could have evolved on Titan itself.
Another possible home for life is the small moon Enceladus. It's only about 300 miles in diameter, but it has all the ingredients for life: water, energy, and carbon-based chemical compounds.
The Cassini spacecraft discovered the moon's interesting chemistry earlier this year. It found that water vapor and ice are spewing out of large cracks near the south pole -- cracks that look like tiger stripes. The gravity of Saturn and its other moons heat and twist Enceladus, warming its interior and creating the cracks.
The escaping gases give Enceladus a thin atmosphere of water vapor mixed with nitrogen, carbon dioxide, and other chemicals.
The surface gravity of Enceladus is weak. That allows much of the moon's water to escape into space, where it may supply fresh ice to one of Saturn's rings.
Look for Saturn near the Moon tonight. They rise in mid evening, soar high overhead later on, and stand high in the west at dawn. www.stardate.org
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