About Enceladus

• It was discovered in 1789 by William Herschel. 
• Sixth largest moon of Saturn
• Diameter: About 500 kilometers (310 miles), making it the sixth-largest moon of Saturn.
• Surface: Highly reflective icy surface with fresh snow deposits hundreds of meters thick.
• Orbit: Located within Saturn's E Ring and orbits in a nearly circular path and is tidally locked, meaning the same face always points toward Saturn.
• Subsurface Ocean: Has a global saltwater ocean beneath an ice shell estimated 30-40 km thick.
• Geological Activity: Active geyser-like plumes eject water vapor, ice particles, organic compounds, and molecular hydrogen from fissures near its south pole.

Recent discoveries

• NASA's Cassini mission data revealed fresh, complex organic molecules from Enceladus' subsurface ocean, including aliphatic, cyclic ester, and ether families, indicating active organic chemistry that could support biochemical processes.

• Evidence suggests Enceladus' ocean has remained stable over geological timescales, a crucial factor for the potential development and persistence of life.
• Cosmic rays may drive radiation-based chemistry within Enceladus’ ocean, providing a possible energy source for life in subsurface environments beyond sunlight.
• The mass and composition of Enceladus' plume ejecta have been re-evaluated, showing more material expelled than previously estimated.
• Hydrothermal activity on the ocean floor is confirmed to create mineral-rich water interactions, analogous to Earth's deep-sea vents, which could sustain microbial ecosystems.
• ESA and NASA prioritize planning future missions to further explore Enceladus by sampling its plumes and potentially landing near the south pole to analyze ocean chemistry in situ.

New models help explain the moon's internal heat generation and ice shell dynamics, crucial for understanding its habitability potential.

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