AP, Science Now, etc: Saturn’s dusty halo is smudging a moon, it appears. But is it really a ring?
Saturn’s rings are magnificent things, bright and unmistakable. And those of Neptune and Jupiter are faint, but are narrow circular lanes that fit the geometric implication of “ring.” But one wonders whether NASA’s proclamation of discovery of a vast new ring of Saturn isn’t just a tad bit misleading. The discovery is notable enough: a belt of diffuse dust so extensive that its thicker regions, if bright and visible to the eye, would extend across a patch of Earth’s nighttime sky as extensive as two full moons side by side. But a ring? You can’t see it, and it hasn’t sharp edges. This looks like poaching on a term with a specific resonance in the mind to draw media and public attention to something different. Sort of like putting pictures of beautiful young models in ads for shaving cream, cars, or beer. Speaking of beautiful, that artist’s impression is striking, in part for the background nebulosities. Very spacey.
And most outlets swallowed it. One that did not is AAAS‘s ScienceNOW, where veteran space writer Richard Kerr has it under another kind of hed: Mystery Solved: The Dark Side of a Moon. This one suggests that Kerr took a moment to think the news’s content through for himself – and thus take ownership of the story that would run under his name. It’s not this wispy dusty disk that he sees as the diverting news, but the odd face of Saturn’s moon Iapetus. It appears that orbital mechanics sends some of the dust – whose plane is tilted sharply compared to most of the rest of the Saturnian system and orbits in pretty much the opposite sense – paints one side of the tidally-locked moon dark while the other icy side shines strikingly bright.
The news arises from a meeting of the AAS’s Division of Planetary Sciences, in Puerto Rico, and a report by university-based users of NASA’s Spitzer Space Telescope. The group also is describing the results in a future issue of Nature – which has lifted its embargo, posted it, and where press material also advertises it as the solar system’s largest ring.
It seems as though a better phrasing would be that far beyond the famous rings, a small moon (not Iapetus, but eccentric Phoebe) has spread a huge disk or belt of hyperfine dust. Most accounts do get around to the Iapetus sand-painting angle, which NASA’s release and Nature’s press bulletin also ranks as a secondary aspect of the story’s significance.
Playing up the discovery as a ring is not any sort of egregious mistake. It is huge, and it is sort of a ring, if one considers a broad rim on a hat a ring.
Other stories:
- AP: NASA telescope discovers giant ring around Saturn ;
- Science News – Ron Cowen: Largest Known Planetary Ring Discovered ; First story out, covered from the meeting.
- Reuters: Huge new ring spotted around Saturn ;
- Brisbane Times – Jennie Curtin: Saturn’s supersized ring has an icy, eccentric orbit ;
- Telegraph (UK) New ring discovered around Saturn is the largest in the Solar system ; Hmm. The asteroid belt is as much ring as this is. So perhaps are the dust-filled orbital paths of comets. And they are larger.
- Scientific American – John Matson: Astronomers Discover Solar System’s Largest Planetary Ring Yet around Saturn ; Smart qualification: planetary ring.
- Space.com – Andrea Thompson: Enormous New Ring Found Distantly Orbiting Saturn ;
- National Geographic – Ker Than: New Saturn Ring Is Largest Known; May Solve Moon Puzzle ; Hmm. Not sure if its invisible because the material is dark, or because it’s so wispy. But good double-fisted hed on what this means.
- Nature – Michelle Grayson: Huge ‘ghost’ ring discovered around Saturn ; That’s a good compromise. A ghost ring.
Grist for the Mill:
JPL/NASA Press Release ; U. Maryland Press Release ;
- Charlie Petit
