A large-scale crater rides the terminator between day and night on Dione, a 700-mile-wide moon of Saturn. The moon’s signature “wispy lines” can be seen on the sunlit side. These are long fractures in the moon’s surface, exposed ice-covered cliffs hundreds of feet high. Scientists believe they indicate past tectonic activity, or possibly the…
Tag: Saturn
Eclipsing Mimas
This animation, made from a series of 8 raw images taken by Cassini on May 14, shows Saturn’s moon Mimas being eclipsed by another object…..a neighboring moon, perhaps? It’s not mentioned, but it definitely seems to be something of similar size, and round. Mimas is best characterized by its large-scale Herschel crater in its…
Into the Shadows
Saturn’s shadow falls upon its rings in this image acquired by Cassini on March 20, 2009. Reflected light from the southern hemisphere of the planet illuminates part of the normally transparent C ring, silhouetting the ring segments there. This image is an approximate true-color view of the planet and rings as might be seen…
Wave Rider
4.3-mile-wide Daphnis races along its track, the 26-mile-wide Keeler Gap in Saturn’s A ring, stirring up sinuous edge waves in the ring material behind and before it. Not only does the shepherd moon cast a small shadow onto the ring, but so do the crests of the waves it’s creating! It’s a wonderful little…
Capturing Pan’s Shadow
Cassini took this photo yesterday, May 9th, as 16-mile-wide shepherd moon Pan passed along its path through the Encke Gap. Its shadow falls upon the A ring, pointing toward Saturn. (I colored the image to approximate visible light coloration based on other true-color calibrations. The original raw image can be seen here.) Pan is…
Through the Clouds
A background star is caught within Titan’s atmosphere, as seen by Cassini during its May 5 flyby, seemingly trapped between the cloudtops and high haze layer that surrounds the moon. Eventually the star sinks behind the enshrouding clouds, its light eclipsed by the moon. See image at right. These images are raw and uncalibrated….
A Hazy Shade of Titan
Cassini looks down onto Titan’s north pole, its camera revealing the high-level atmospheric haze that encircles the 3,200-mile-wide moon. This image was shot in visible violet light on March 27, 2009, using Cassini’s wide-angle camera. The spacecraft was 122,000 miles away from Titan at the time. The sunlit part of Titan is the side that…
Sister, Sister
Cassini turns its camera towards the Pleiades, a familiar star cluster often called the Seven Sisters. Actually containing much more than seven stars (look at it through binoculars some time!) the Pleiades consists of many young, hot blue stars in close arrangement approximately 440 light-years from our solar system. They can be seen easily…
Shadow Facts
A moon’s shadow falls upon ring after ring in this image, taken on April 29 by Cassini. Varying brightnesses and compositions of ring segments scatter light differently, as shown above. With Saturn’s spring equinox (August 11) getting closer every day, the ringplane – and orbital plane of many of its moons – are approaching a perpendicular…
Streaming Along
Another animation, this time from April 24, 2009, made from 116 raw images from the Cassini spacecraft. The orbiting Cassini focused its camera on Prometheus as it dipped into the F ring and back out again, pulling the icy dust into wispy strands with its passing. Prometheus’ oblong shape can be seen clearly here…it…
A Rainbow of Rings
Saturn’s amazing and beautiful rings cast their shadow over its cloud tops, dividing its north and south hemispheres in this image from Cassini. The spacecraft was 621,000 miles from the planet when it took this picture on February 28, 2009. Image credit: NASA/JPL/Space Science Institute
Regarding a Ring
Made from 127 raw images received from the Cassini spacecraft on April 17th, this sequence shows the varied structure of the F ring as it is influenced by passing moons, clumps of material and its own twisted composition. Initially calm, with only background stars marking the passage of time, a passing moon outside the…
Lights in the Dark 