One of the Cassini orbiter's latest pictures from Saturn highlights the wide spectrum of the ringed planet's moons. In this view, Titan looms large ... as befits its status as the solar system's second-biggest moon (Jupiter's Ganymede is a bit bigger). At 3,200 miles across, Titan is bigger than the planet Mercury. It's also the only moon in the solar system with a thick, opaque atmosphere.
Then there are the two other moons in the picture: You can probably spot 313-mile-wide Enceladus off to the right, silhouetted against Saturn's disk. But can you see 50-mile-wide Pandora? It's off to the far left, just outside Saturn's thin F ring. The tiny moon's brightness has been enhanced by a factor of two in this image, and yet it's barely perceptible unless you move your browser window around. You could easily mistake it for a speck of dust on your screen.
Believe it or not, Pandora is nowhere near the smallest of Saturn's more than 60 moons. Many of those moons measure less than five miles across, and yet they can be spotted by powerful telescopes on Earth. A couple of years ago, the Cassini probe identified a moonlet hidden in one of Saturn's rings that spans only about a third of a mile. That's a testament not only to Saturn's spectrum of satellites, but also to Cassini's powers of observation.
This particular view was captured on Jan. 15 by Cassini's wide-angle camera, at a distance of 524,000 miles from Titan. Click on the links below for still more stunning views from the Saturn-circling spacecraft:
- A double scoop of Saturn's moons
- It's a Saturnian moonapalooza!
- See what's hot on Saturn moon
- Greatest hits from Cassini
Still can't see Pandora? That may be because you're looking at the smaller version displayed on Cosmic Log. The picture on Photoblog is 50 percent bigger, which makes it easier to see the tiny moon on the left if you look really, really closely.
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