Planetary scientist Carolyn Porco shows images from the Cassini voyage to Saturn, focusing on its largest moon, Titan, and on frozen Enceladus, which seems to shoot jets of ice.Enceladus [en-SELL-ah-dus] is one of the innermost moons of Saturn. It is quite similar in size to Mimas, but has a smoother, brighter surface. Enceladus reflects almost 100 percent of the sunlight that strikes it. Unlike Mimas, Enceladus displays at least five different types of terrain. Parts of Enceladus shows craters no larger than 35 km in diameter. Other areas show regions with no craters, indicating major resurfacing events in the geologically recent past. There are fissures, plains, corrugated terrain and other crustal deformations. All of this indicates that the interior of the moon may be liquid today, even though it should have frozen aeons ago. It is postulated that Enceladus is heated by a tidal mechanism similar to Jupiter's moon Io. Enceladus is perturbed in its orbit by Saturn's gravitational field and by the large neighboring satellites Tethys and Dione.Could there be intelligent life on other planets? This question has piqued imagination and curiosity for decades. Explore the answer with the Drake Equation -- a mathematical formula that calculates the possibility of undiscovered life. Out of billions of galaxies and billions of stars, how do we find Earth-like habitable worlds? What is essential to support life as we know it? Ariel Anbar provides a checklist for finding life on other planets.Life on Earth requires three things: liquid water, a source of energy within a habitable range from the sun and organic carbon-based material. But life is surprisingly resilient, and organisms called extremophiles can be found in hostile living conditions (think extreme temperatures and little access to oxygen). Louisa Preston argues why extremophiles give astrobiologists hope for life in the universe.In August 2012, the Curiosity rover landed on Mars. The landing itself was a huge achievement and required a lot of forethought and planning by a very smart team. In this TED Youth 2012 Talk, Bobak Ferdowsi, the mohawked member of that team, outlines various aspects of a Mars landing, including the Seven Minutes of Terror.Enceladus is the sixth-largest of the moons of Saturn. It was discovered in 1789 by William Herschel.Enceladus seems to have liquid water under its icy surface. Cryovolcanoes at the south pole shoot large jets of water vapor, other volatiles and some solid particles (ice crystal, NaCl etc) into space (total approximately 200 kg per second). Some of this water falls back onto the moon as "snow", some of it adds to Saturn's rings, and some of it reaches Saturn. The whole of Saturn's E ring is believed to have been made from these ice particles. Because of the apparent water at or near the surface, Enceladus may be one of the best places for humans to look for extraterrestrial life. By contrast, the water thought to be on Jupiter's moon Europa is locked under a very thick layer of surface ice.

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