Herschel: Water at Ceres

What’s that? You never met Herschel?

Via ESA:

ESA’s Herschel space observatory has discovered water vapour around Ceres, the first unambiguous detection of water vapour around an object in the asteroid belt.

Water!With a diameter of 950 km, Ceres is the largest object in the asteroid belt, which lies between the orbits of Mars and Jupiter. But unlike most asteroids, Ceres is almost spherical and belongs to the category of ‘dwarf planets’, which also includes Pluto ….

…. [U]sing the HIFI instrument on Herschel to study Ceres, scientists have collected data that point to water vapour being emitted from the icy world’s surface.

“This is the first time that water has been detected in the asteroid belt, and provides proof that Ceres has an icy surface and an atmosphere,” says Michael Küppers of ESA’s European Space Astronomy Centre in Spain, lead author of the paper published in Nature.

Although Herschel was not able to make a resolved image of Ceres, the astronomers were able to derive the distribution of water sources on the surface by observing variations in the water signal during the dwarf planet’s 9-hour rotation period. Almost all of the water vapour was seen to be coming from just two spots on the surface.

“We estimate that approximately 6 kg of water vapour is being produced per second, requiring only a tiny fraction of Ceres to be covered by water ice, which links nicely to the two localised surface features we have observed,” says Laurence O’Rourke, Principal Investigator for the Herschel asteroid and comet observation programme called MACH-11, and second author on the Nature paper.

And, really, what can you say? Good show, Herschel. Congratulations, ESA. And thank you. That is really, really cool.

Herschel is named for the guy who discovered Uranus; William Herschel also identified infrared radiation over two hundred years ago. This latest announcement is one of the satellite’s last dramatic gifts; Herschel ran its course, with final commands sent in June, 2013.

It was certainly a good run. And there are probably myriad little gifts remaining to be discovered in the data.

Talk about a show. Water at Ceres. Makes as much sense as anything else, to be certain, but it is also good to know.


Rock Hyrax a Trivial Bonanza

P. capensis (rock hyrax)It sounds lonely: “Modern hyraxes are members of the Procaviidae family, the only living family within the Hyracoidea.” Venerable, primitive mammals, rock hyraxes are full of trivial surprises, as Mary Bates explains for Wired Science’s Zoologic:

The rock hyrax (Procavia capensis) is full of surprises. While it looks like a slightly more robust version of a guinea pig, it’s no rodent. These squat, furry animals are found across Africa and the middle East, where they like to hang out in rock formations and the seemingly inhospitable nooks on sheer cliff faces. Rock hyraxes are gregarious, living in colonies of up to 80 individuals. They grow up to two feet in length and about 10 pounds in weight.

Weird stomachs, tusks to mark their relation to elephants, toenails, scent gland, suctiony feet, and even cameos in the Bible; the note on reproductive glands, though, is actually a bit … (ahem!) scary.

Even so, at two feet long and ten pounds in adulthood, rock hyraxes have managed to develop a reasonably complex language including twenty-one sounds woven into diverse patterns, as well as regional dialectical differences.

Nor is it actually so lonely; Procaviidae may be the last living family of order Hyracoidea, but the rock hyrax has fellows and neigbors, such as the yellow-spotted rock hyrax and two kinds of tree hyrax.

As an additional note, there is apocrypha … not quite a story, not quite a theory … suggesting that the rock hyrax is the root of Hispania, and therefore the animal after which Spanish-speaking culture is named. Stranger things, of course, have happened … at least, I think.

Linkadelic Mess

Molloy, 'Burning Cotton Candy' (detail)
Given that year-end lists are something of a useless cliché, we figure it works just as well to do a junkpile and clear out a bunch of links waiting for some more useful deployment than sitting in a badly-punned directory (URLenmeyer) on the desktop. Thus, in no particular order:pH scale


• Why certain Chinese cat fossils are so fascinating.

Synaptogenesis is a word you will start hearing more often in the near future.

• Sure, it’s a bit old, but A Citizen’s Guide to Understanding and Monitoring Lakes and Streams, from the Washington Department of Ecology, is still relevant.

• There really is a holy grail for dystopic, embittered, supervillainous math geeks.

• Suffice to say, the link file for this one was actually a bad casserole joke. No, really.

• Celebrate the saola, a Vietnamese ox confirmed to still exist after fifteen years out of sight.

• We all heard the cool news about India shooting for Mars?

• The tortoise and the Lego, that’s all you need to know.

• Dinosaurs are human, too. Er, I mean … ah … right. Something about a clumsy dinosaur.

• Apparently, the Milky Way wobbles and flutters. (If you like the technical stuff, the arXiv file is available.)

Ultraviolet … Imaging … Spectrograph; maybe not a band name, but certainly worthy of being an album cover. Vinyl. Twelve inch.

Spiders. Might as well get used to ’em.

• Have you met Juno?

• Ice, water, steam … how about plasma? And no, plasma water is not a sports drink … yet.

• Here there be monsters.Uranus Trojan Lagrange

Uranus Trojan Lagrange is not a band name. It’s something even cooler.

• Then again, Martian eclipse would be a good band name, too.

xkcd on ice.

Teller talks Tim’s Vermeer.

• Various processes more complicated than explanations are worth keep bringing to mind an old episode of Radiolab, about laughter.

Detail of PIA050760