Little Tethys is getting a lot of face time in front of Cassini’s lens. In this photo, from a raw image taken on October 17, Tethys passes across the hazy face of her much larger sister, Titan. 662-mile-wide Tethys is dwarfed by the 3,200-mile-wide Titan, although the distance that separates them in this image reduces…
Tag: solar system
Just Passing By
Tethys, shown in my previous post, orbits Saturn outside the rings in this animation made from 17 raw images taken by Cassini. After passing the dark side of Saturn Tethys follows the curve of the rings, and is passed on the “inside track” by the smaller Mimas (top). Meanwhile another moon, perhaps Atlas or Pandora,…
Full Moon
Here’s an amazing portrait of Tethys, a 662-mile-wide, airless and heavily-cratered moon of Saturn. The photo was taken by Cassini on October 14, 2009, with the moon fully lit by the sun. Its high reflectivity (albedo) indicate a large amount of ice in its composition. I adjusted the image to bring out the details in…
A Rhea View
Here’s an amazingly detailed view of the extensively cratered surface of Rhea, Saturn’s second-largest moon, taken during a particularly close encounter by Cassini on October 13, 2009. About 950 miles wide Rhea is less than a third the size of Titan, Saturn’s largest moon. Unlike Titan, Rhea has no atmosphere at all to speak of…
A Cratered Crescent Composition
The crescent of Saturn’s moon Tethys hovers serenely over a dimly-lit ringplane in this raw image, taken by the Cassini orbiter on October 11, 2009. Frigid, airless and heavily-cratered, Tethys is mostly composed of water ice and rock. It is 662 miles wide. Image: NASA/JPL/SSI
Can’t Catch Me!
Windswept Martian dunes create a somewhat humanoid, running gingerbread-man figure in this image from the HiRISE camera aboard the Mars Reconnaissance Orbiter. The dunes reside within a crater in the southern hemisphere of Mars. This week, the University of Arizona released thousands of new images from their HiRISE (High Resolution Imaging Science Experiment) observations, taken…
Ring King
The bright band in this image is a cross-section of a massive new ring discovered around Saturn, a cold, diffuse and incredibly thick band of material orbiting the planet 3.7 million miles out…..much farther out than any of the other rings and farther away even than most of Saturn’s moons. The ring is so…
First Rock From The Sun
While approaching the planet for the third flyby of its mission, the MESSENGER spacecraft took this photo of Mercury, crescent-lit by the sun and showing terrain that has never been imaged before. The region along the planet’s limb, the brightest area seen here, had yet to be mapped by the spacecraft’s cameras. It contains many…
Saturn in the Spring
The Cassini Imaging Team has released this image, a stunning portrait of Saturn made from 75 separate wide-angle exposures taken during the ringed planet’s spring equinox on August 12, 2009. The specific angle of sunlight during the equinox makes the shadow of Saturn’s expansive rings appear as a pencil-thin line across the cloudtops at the…
Look on the Bright Side
Another view of Saturn’s moon Iapetus (see previous post) shows the brighter surface illuminated by the sun, with a section of the darker surface visible near the moon’s equator. This dual-coloration of the 914-mile-wide moon was first observed by Giovanni Cassini in 1671. Noticing that the moon was only visible when on the western side…
Spokes and Shadows
This animation, made up of several raw images from the Cassini spacecraft, shows the mysterious features known as spokes in Saturn’s B ring. These spokes, thicker regions of material within the otherwise uniform rings, were first observed by Voyager in 1980 and have yet to be have their mechanics explained by scientists. Theories range from…
Into the Blue
Discovered by philosophy professor Ted Stryk in the archives of Voyager 2 image data, four separate images were combined to show the shadow of Despina – lightened for better visibility – crossing over the sky blue face of Neptune. Neptune, now officially the outermost planet in our solar system, was visited by Voyager 2 in…