Pluto Might Have Rings

Related story. The links on Sciam appear to be dynamically generated, but perhaps they're just changed every day or something. You may wind up having to go into the main page and hunt down this article. That's what I had to do.

Two New Moons--and Maybe Some Rings--for Pluto
by David Biello
February 23, 2006
Scientific American
"We used Hubble's exceptional resolution to peer close to Pluto and pick out two small moons that had eluded detection for more than 75 years," says Hal Weaver, an astrophysicist at Johns Hopkins University and the discovery team leader. "That was somewhat surprising because ground-based observers had been trying for more than a decade to find new satellites around Pluto," adds astronomer Max Mutchler of the Space Telescope Science Institute, the first to see the moons in Hubble's images. Based on their brightness--and assuming that their surfaces are about as reflective as Charon's--the scientists believe the two moons are roughly 38 miles and 29 miles in diameter. Given that they share Pluto's distance from the sun--roughly three billion miles--but are 4,000 times fainter, it is not surprising that the satellites eluded detection until now, the researchers say.

The researchers say that it is somewhat surprising that they hadn't been seen before, but not surprising that they'd eluded detection? Either the writer or the editor should have noticed that discrepancy.

This SA story about the moons is also recent (FR has at least one topic) and has different moon size data than Nick's article from Space, and that's interesting. From 2003:

Pluto's Other Moons:
Why They Might Exist and Who's Looking
by Robert Roy Britt
6 May 2003
Earlier this year, around the time New Horizons was approved by NASA, Stern and colleagues announced they would conduct a search for moons of Pluto by year's end. Pluto has one known moon, Charon which, at 745 miles (1,200 kilometers) wide is more than half the size of Pluto and the largest satellite in our solar system relative to its planet... Pluto may have some distinct advantages over Earth in the satellite-garnering department... "The probability of a two-body gravitational capture is phenomenally low," Stern said, even for objects that pass reasonably close... It's more likely, however, that one or more other satellites could have formed directly around Pluto during its birth, Stern said. Or the planet could harbor a cloud of small objects that were broken up from a collision that shattered a satellite of Pluto long ago... Pluto, less massive but more distant from the Sun, could retain a satellite orbiting as far as 620,000 miles (1 million kilometers) away.

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