Cassini Spacecraft

Below is a photograph that was originally featured on the fantastic Astronomy Picture of the Day site by NASA . It shows what the Cassini spacecraft saw as it performed a recent "fly-by" of one of Saturn's moons, Enceladus ; giant jets of ice erupting from the surface. As always, click to enlarge. Read Full Story

The eccentricity of Saturn's orbit around the sun may be responsible for the unusually uneven distribution of methane and ethane lakes over the northern and southern polar regions of the planet's largest moon, Titan according to researchers at the California Institute of Technology. On Earth, similar "astronomical forcing" of climate drives ice-age cycles. Liquid hydrocarbon–filled lakes in Titan's northern high latitudes cover 20 times more area than lakes in the southern high latitudes. There are also significantly more partially filled and now-empty lakes in the north, as revealed by imaging data taken by NASA's Cassini spacecraft, which has been surveying Saturn and its moons ... Read Full Story

Researchers at the California Institute of Technology (Caltech) suggest that the eccentricity of Saturn's orbit around the sun may be responsible for the unusually uneven distribution of methane and ethane lakes over the northern and southern polar regions of the planet's largest moon, Titan. On Earth, similar "astronomical forcing" of climate drives ice-age cycles. A paper describing the theory appears in the November 29th advance online edition of Nature Geoscience. As revealed by Synthetic Aperture Radar (SAR) imaging data taken by NASA's Cassini spacecraft, which has been surveying Saturn and its moons since 2004, liquid hydrocarbon-filled lakes in Titan's northern high latitudes cover 20 ... Read Full Story

An aurora, shining high above the northern part of Saturn, moves from the night side to the day side of the planet in this movie recorded by Cassini. These observations, taken over four days, represent the first visible-light video of Saturn's auroras. They show tall auroral curtains, rapidly changing over time when viewed at the limb, or edge, of the planet's northern hemisphere. The sequence of images also reveals that Saturn's auroral curtains, the sheet-like formations of light-emitting atmospheric molecules, stretch up along Saturn's magnetic field and reach heights of more than 1,200 kilometers (746 miles) above the planet's limb. These are the tallest ... Read Full Story

Saturn's moon Prometheus, orbiting near the streamer-channels it has created in the thin F ring, casts a shadow on the A ring in this image taken a little more than a week after the planet's August 2009 equinox. Potato-shaped Prometheus (86 kilometers, or 53 miles across) periodically creates streamer-channels in the F ring, and the moon's handiwork can be seen on the left of the image. The novel illumination geometry that accompanies equinox lowers the sun's angle to the ringplane, significantly darkens the rings, and causes out-of-plane structures to look anomalously bright and cast shadows across the rings. These scenes are possible only during ... Read Full Story