Iapetus: Saturn’s Stained Moon

Saturn’s “yin-yang” moon Iapetus (pronounced eye-AH-pe-tus) is seen in this image, a color composite made from raw images acquired by Cassini’s narrow-angle camera on March 11, 2017. The color difference on Iapetus is due to a fine coating of dark material that falls onto its leading hemisphere, sent its way by the distant moon Phoebe traveling within the recently-discovered giant diffuse…

A Northern View of Saturn’s Stained Moon Iapetus

Here’s a raw image of Saturn’s moon Iapetus, looking down on its northern hemisphere from Cassini on March 31, 2015. The moon’s signature two-toned coloration is evident as its bright icy surface is partially coated by dark material, thought to have been ejected from distant neighbor Phoebe. Iapetus is 914 miles (1,471 km) in diameter, or…

The Curious Central Peaks of Iapetus

The curious, 20-km tall central ridge of Iapetus, a.k.a. the Voyager Mountains Saturn’s 914-mile (1471-km) -wide Iapetus (pronounced eye-AH-pe-tus) has a particularly curious feature: a chain of 20-kilometer (12-mile) high mountains encircling the moon’s equator. On the anti-Saturnian side of Iapetus, the ridge appears to break up, forming distinct, partially bright mountains. The Voyager I…

The Tao of Iapetus

With a leading side dark as charcoal and trailing side bright white, the 914-mile-wide Iapetus is literally the yin-and-yang of Saturn’s family of moons. The color variation on Iapetus is due to the fine coating of dark material that falls onto its leading hemisphere, possibly sent its way by smaller, distant Phoebe traveling within the…

Eye on Iapetus

Saturn’s moon Iapetus shows its bright (and lumpy!) side in this image from Cassini, taken on November 29. Like many people I know, 914-mile-wide Iapetus has a dark side and a bright side, its bright surface composed of water ice and rock and its dark half a coating of material, most likely from the newly-discovered…

Cassini Marks Ten Discovery-Filled Years at Saturn

Just a week after Curiosity celebrated its first Martian year in Gale Crater and we have yet another milestone anniversary in Solar System exploration: as of 10:48 p.m. EDT tonight Cassini will have been in orbit around Saturn for a full decade! “There are times when human language is inadequate, when emotions choke the mind, when the magnitude…

A Cosmic Quotation Mark? No, It’s Just Another Moon of Saturn

What looks like a single open-quote (or backwards comma) is really Saturn’s two-toned moon Iapetus, seen here in RGB composite color made from raw images acquired by Cassini on Aug. 30 from a distance of about 1.5 million miles. With a leading side stained a dark reddish hue and a trailing side bright white, the…

High Over Hyperion

The Cassini spacecraft passed by Saturn’s spongy-looking moon Hyperion yesterday, August 25, and returned some very dramatic images like the one seen here – fascinating! At 15,000 miles this was Cassini’s second-closest approach to Hyperion. It will pass by again on September 16 at just over twice that distance. The closest it has come to Hyperion…

Look on the Bright Side

Here’s a color-composite image of Saturn’s two-toned moon Iapetus; its Saturn-facing light side is seen here facing to the lower left. Iapetus is 1,471 km (914 miles) wide. The raw images were taken by the Cassini spacecraft on June 6, 2011 and received on Earth June 8, 2011. The camera was pointing toward Iapetus from…

The Light of a Distant Sun

Since I haven’t posted in a while, I thought I’d put up this image I was playing with last week…it’s a raw image of Saturn’s moon Iapetus combined with a bit of a “glow” from an off-frame Sun and a few stars thrown into the background. Just for curiosity’s sake. 🙂 914-mile-wide Iapetus was discovered…

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…

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…