- Attachment: Enceladus image
- The surface of Enceladus is water ice. In 1980 Voyager 2 spacecraft photographed Enceladus’ craters, narrow valleys, groves and ridges. It found sharp-edged canyons 120 miles long, 5 miles wide, and ½ mile deep. All later to be discovered as water ice.
- Enceladus orbits Saturn n the densest part of the “E” ring 148,000 miles away from Saturn. Enceladus is so small the escape velocity needed to leave its gravity is only 500 miles per hour. It reflects nearly 100% of the sunlight that hits its surface. Our Moon reflects 7%. Enceladus absorbs so little sunlight its average temperature is -337 F.
- When the Cassini spacecraft arrived in 2005 it found geysers were erupting from the surface. The geysers were mostly water vapor and ice particles but they spewed 300 miles high above the surface. Enceladus is only 311 miles in diameter, the geysers are just as tall.
- Enceladus orbits Saturn is 32.9 hours and has a 2 to 1 orbital resonance with the inner moon Mimas. It also has a 2 to 1 resonance with the outer moon Dione. These resonances create tidal forces on Enceladus that push and pull its surface, similar to how the Moon pushes and pulls the oceans on Earth.
- In 2008 Cassini completed a flyby passing just 35 miles above the surface. As it flew through a geyser ejection it measured water, nitrogen, methane, carbon dioxide, ammonia and solid particles. It found hydrocarbons propane, ethane and acetylene. Ammonia is a potent anti-freeze that could keep water in a liquid state down to -136 F.
- In 2011 astronomers detected an electric current of high-intensity electrons surging between Enceladus and Saturn. The electric charges create an aurora over Saturn.
- There is more to learn. An announcement will be made shortly, stay tuned.
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