This is a color image of Saturn’s moon Tethys I made from raw images acquired by Cassini on Feb. 1, 2017 in visible-light color channels. It shows the moon’s sunlit leading side—the face that aims in the direction that it moves in its orbit around Saturn. (Click image for a larger version.) While this icy moon is…
Category: Saturn’s Moons
Yes, Obi-Wan, That’s a Moon
Saturn’s 250-mile-wide icy moon Mimas shines in direct sunlight and reflected light from Saturn in this image, a composite of raw images acquired by NASA’s Cassini spacecraft on Jan. 30, 2017 and received on Earth today, Feb. 1. This is a bit of a “Frankenstein” job I made, assembled from five separate narrow-angle camera images taken in…
Cassini Has Just Taken the Best Picture of Daphnis Yet!
Hello, Daphnis! On January 16, 2017, the Cassini spacecraft captured the best photo yet of Daphnis, a 5-mile-wide shepherd moon that orbits Saturn inside the Keeler Gap at the outermost edge of the A ring (and also just so happens to be my personal favorite moon of Saturn!) The raw image arrived on Earth today, and…
Revisit Our First (and Only) Landing on Titan
When you think of spacecraft landings on other worlds, you probably first think of Mars, the Moon, Venus, and comet 67P (if you’ve been following along over the past couple of years.) But—in addition to the asteroid Eros and hard impacts on a comet and Mercury—Saturn’s moon Titan was also visited by an alien (i.e.,…
Light and Dark: the Two Faces of Dione
Saturn’s moon Dione (pronounced DEE-oh-nee) is a heavily-cratered, 700-mile-wide world of ice and rock, its surface slashed by signature “wispy lines” that mark the bright faces of sheer ice cliffs. But Dione has some strange colorations too, evident here in a global map created in 2014 from Cassini images. Its leading half—the side that faces “forward” as…
Bright Clouds Make a Comeback on Titan’s North Pole
Floating high above Titan’s hydrocarbon lakes, wispy clouds have finally started to return to the moon’s northern latitudes…but in much less numbers than expected. Models of Titan’s climate have predicted more cloud activity during early northern summer than what Cassini has observed so far, suggesting that the current understanding of the giant moon’s changing seasons is…
Watch Saturn’s Moons Race Inside the Rings
Round and round they go… the animation above, made from 14 raw images taken by NASA’s Cassini spacecraft on August 23, 2016, shows the moons Prometheus and Atlas orbiting Saturn within the Roche Division gap between its A (top right) and F (center) rings. The gravitational tug of Prometheus (92 miles / 148 km long) is strong…
Enceladus’ Jets: the Farther They Are, the Harder They Spray
A crowning achievement of the Cassini mission to Saturn is the discovery of water vapor jets spraying out from Enceladus‘ southern pole. First witnessed by the spacecraft in 2005, these icy geysers propelled the little 320-mile-wide moon into the scientific spotlight. After 22 flybys of Enceladus during its nearly twelve years in orbit around Saturn, Cassini has gathered enough data to determine…
And the Award for Leading Trojan Moon Goes To…
Drumroll please… the little moon Telesto! (You like it, you really like it!) This image, captured by Cassini on Jan. 14, 2016, shows Saturn’s moon Telesto – a “leading trojan” of the much larger satellite Tethys. A trojan moon is one that orbits a parent body within the same path as a more massive satellite,…
Cassini Has Made Its Last Pass by Enceladus. Here Are the Pictures.
After nearly eleven and a half years in orbit around Saturn the Cassini spacecraft has made its last-ever targeted flyby of Enceladus, the 320-mile-wide moon of Saturn that has intrigued scientists and the public alike with its active water ice geysers for more than a decade since their discovery. On Saturday Dec. 19, 2015, Cassini performed its E-22…
Soar Over the Surface of Tethys with Cassini
On Nov. 11, 2015, NASA’s Cassini spacecraft passed relatively closely by Saturn’s moon Tethys, one of the ringed planet’s larger icy satellites. The animation above was made from 29 raw images acquired with Cassini’s narrow-angle camera as it passed by; you can see part of the incredibly cratered and ancient surface of this 662 mile (1,065 km) wide…
Pics Are In from Cassini’s Flyby Through Enceladus’ Plumes!
On Wed. Oct. 28 Cassini performed its lowest-altitude dive yet through the icy plumes of Enceladus, coming just 30 miles from the moon’s surface — that’s only about 6 times higher than a commercial airliner at cruising altitude. But, traveling over 19,000 mph relative to Enceladus (which is 38 times faster than a jet plane!) the pass was…
Lights in the Dark 