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What would it look like to watch Daphnis fly past?

Maybe something like THIS:

Daphis by Erik Svensson (All rights reserved)

Daphnis by Erik Svensson (All rights reserved)

What a great combination: Daphnis (my favorite moon) and an artist’s interpretation of what it might look like to see it whiz past as it travels around Saturn inside the Keeler Gap, sending up waves in the rings as it goes! The image is by Erik Svensson, who came across my recent article on Universe Today and was reminded of an illustration he’d made a year ago.

After contacting me about it, I felt Erik’s work definitely belonged in the article as well as here on Lights in the Dark!

Read the article on Daphnis here, and see more of Erik’s work here.

Daphnis Is Back!

Daphnis’ gravity carves waves into the edges of the Keeler gap on Nov. 11, 2012

It’s been a while since I posted an image of my favorite moon of Saturn, but while looking through some recent raw images returned by the Cassini spacecraft I spotted it: Daphnis, the little sculptor shepherd moon!

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Daphnis in Full Color

Color-calibrated image of Daphnis and Saturn's rings by Gordan Ugarkovic

If you’ve been following along with Lights in the Dark since the beginning, you may know that this is one of my favorite subjects of space imagery: the shepherd moon Daphnis, traveling in its orbit around Saturn within the 26-mile-wide Keeler Gap. Recently color-calibrated by Gordan Ugarvovic, this is a true-color version of an image captured by Cassini on July 5, 2010. It was Cassini’s closest approach to the 4.5-mile-wide moon.

What makes Daphnis so interesting is its effect on the edges of the gap. As it travels its gravity affects the icy bits of ring material, churning them up into waves and scalloped edges before and behind it. These waves can rise up considerably into peaks and valleys, some reaching over a mile or two above the ring plane! Now that would be quite a dramatic sight to see close-up!

This is a great color version of an image I posted about shortly after it was first acquired. A new image from Gordan is always a treat!

Image: NASA / JPL / Space Science Institute / Gordan Ugarkovic

Prime PDS Picks

Saturn's multi-colored atmosphere seen by Cassini on April 30, 2010

Every six to nine months or so the Cassini Imaging Center dumps orbiter image data into NASA’s Planetary Data System, or PDS. This data is accessible to anyone with an internet connection, but it can be a little awkward to find exactly what you’re looking for (unless you’re familiar with the technical nomenclature of the dozen imaging filter codes and timestamps of Cassini data…in which case, dig in!) Luckily the SETI institute has set up a more user-friendly search engine that allows desktop astronomers to zero in on image collections with less data entry involved.

(More photos after the jump…)

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Ring Racer (Take Two)

I came across this image today while going through the latest Cassini PDS (Planetary Data System) release, and remembered how excited I was to see it the first time when it came in last June. If you missed it, here it is again (with an image fresh off the PDS!)

Daphnis churns up the edges of the Keeler Gap

Man, I just LOVE this stuff.🙂

This has to be one of the coolest images yet of one of my favorite subjects: Saturn’s moon Daphnis casting a shadow and riling up the rings as it travels along the 26-mile-wide Keeler Gap, a channel it keeps clear around the outer edge of the A ring. The image above is a cropped and rotated version of a raw image sent back from the Cassini spacecraft today.

The four-and-a-half mile wide Daphnis was first seen by Cassini in 2005. Read the rest of this entry

From the LITD Archives: Wave Forms

Daphnis makes some waves

Daphnis makes some waves

(Originally posted on June 27, 2009) Cast shadows reveal some interesting structure in the waves sent up by little Daphnis in this image, taken by the Cassini spacecraft on June 26, 2009.

Daphnis orbits Saturn within the 26-mile-wide Keeler gap in the A ring. Its gravity disrupts the edges of the gap, carving scalloped edges in the ring material and also, as was discovered during this year’s approaching spring equinox, sends the material upwards (and probably downwards as well) in mile-high waves.



The shadows cast by these waves are now visible because of Saturn’s current angle in relation to the sun. The length of the shadows indicate that the waves can rise as high as 2-3 miles above the rings. Daphnis, discovered in 2005, is just over 4 miles wide.

Sharp crests and ridges in the waves are made evident by their shadows, as is what appears to be a diffuse spray of particles at the front of the second wave just behind Daphnis (the moon is moving upwards in this image).

This is a raw image, received today, and has not been calibrated or validated. See more images on the Cassini imaging team site here.



Every now and then I’ll be digging through my archives – now that I have a decent amount of them! – and reposting some of my particular favorites. Because it’s not just about what’s new, its about what’s still happening. Out there…in the dark.

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