Lotsa ink, two story batches on red dwarf stars! : One has a planet with a maybe-wet atmosphere; cosmos has kazillions more stars like that
Red dwarf stars are little things that keep burning quietly for many billions, make that trillions of years in principle, and then are expected to go out with no explosions or other bother. They don’t get a lot of press. An exception is today. Two entirely different stories bring them up – in one case because one nearby has a singular planet, and in the other, a new analysis implies our universe has an immensely larger population of these barely-burning, or hardly-fusing, orbs than most astronomers ever suspected. Maybe enough to more than double estimates of the number of stars out there of all types. Both pieces of news arise from reports in this week’s Nature.
FIRST UP: A red dwarf called GJ 1214a, only about 40 light years away, was discovered a few years ago to have a close-orbiting, large ‘super-earth’ planet, dubbed by standard practice GJ 1214b. As seen from Earth it happens to be carried across the star’s face, or to transit. Astronomers at the European Southern Observatory and the Center for Astrophysics at Harvard now report, in Nature, isolation of enough of the planet’s spectrum to infer its atmosphere might be full of water vapor. They have, at any rate, excluded a largely-transparent hydrogen and helium outer atmosphere, leaving either an H2O-rich one resembling a superhot sauna, or perhaps an H- and He-dominated miasma laden with volcanic gases or other complex haze. This is interesting because while the planet is large, it may be rocky like Earth or Mars – almost surely no gas giant of the Saturn and Jupiter kind. Ergo, it’s a plausible place where one might suppose life has arisen.
Stories:
- NatureNews – Sid Perkins : A gaze at exoplanet haze ; A slightly technical article, as befits the journal where the really technical paper ran. And it’s good to find Sid still exercising his keyboard on science news after leaving the magazine Science News to go oversee construction of a house with his wife in their native Tennessee.
- AFP – Marlowe Hood: First super-Earth atmosphere analysed: study ;
- USA Today – Dan Vergano: Steamy atmosphere cloaks alien “Super-Earth” ; It’s a blog, and Dan quotes extensively off the paper. I’m unsure I’d be so bold as to declare in the head so unreservedly that it’s steamy air – the paper (and Vergano’s text) simply says that’s the favored surmise but the case is not overwhelming.
- Christian Science Monitor – Pete Spotts: ‘Milestone’ in bid to sniff atmosphere of a ‘super Earth’ light-years away ; This piece is considerably more circumspect than the one immediately above.
- BBC – Jason Palmer: “Super-Earth’ atmosphere measured ;
- Nat’l Geographic – Rachel Kaufman: Earth-size Planet Has Hot and Steamy Atmosphere? ; The planet is mostly hot and probably vaporous water, she reports confidently. But the outer atmosphere remains a mystery, and with most guesses on the noxious side.
- New Scientist / Sky and Telescope – Alan MacRobert : Super-Earth’s atmosphere analysed for first time ;
- Universe Today – Jon Voisey: First Super-Earth Atmosphere Observed ;
- Scientific American – John Matson: Astronomers Get First Peek at Atmosphere of a “Super-Earth” Exoplanet ; A reflective story, starting off with an explanation why this observation is an exercise, honing skills that might be useful with more life-friendly planets. The hed also leads me to wonder (again): Why do the professional astronomers tend to use extra-solar planet, when the perfectly serviceable and semingly unambiguous exoplanet was already in circulation?
Grist for the GJ 1214b Mill:
ESO Press Release ; Harvard-Smithsonian CfA Press Release ; NASA JPL Press Release;
SECOND: The other red dwarf news gets even more coverage. A Yale and Harvard-CfA duo, which used the Keck Observatory in Hawaii to study spectra of several massive elliptical galaxies, concludes they are just oozing light that almost surely comes from red dwarfs. Some 60 percent of their stars, by inference, are such dwarfs. That could double or even triple the total star count. Hmm. Why is not the plural of red dwarf, as in star, not the same as what one might say should Snow White’s little miner pals have been embarrassed? Second off-topic remark: I got talked out of using “Charlie” in my bylines by a distinguished senior reporter at the SF Chronicle in 1972. I’d just gotten one in by Charlie Petit. She said, archly, that some day I might want to write something serious. I buckled. Now one sees that this paper’s Harvard CfA co-author goes by Charlie in all his pubs. Wow. I should’a stuck it out. Of course, maybe this fellow’s given name is Charlie.
Stories:
- AP – Seth Borenstein – Starry starry starry night: Star count may triple ; He is not the only reporter to put the number 300 sextillion in his piece. But he does point out that Carl Sagan’s “billions upon billions” now looks quite modest. The total, however, does have an Earthly, literally human-scale equivalent. It’s about the same as all the cells in all the people on Earth. It doesn’t say whether that’s just the actual human cells or includes the more numerous bacteria and other microbes that inhabit our living bodies. Borenstein wraps the other red dwarf star story, the first up in this post, into his story.
- Los Angeles Times – Amina Khan: Number of stars in universe may be vastly larger than thought;
- Christian Science Monitor/Skymania – Paul Sutherland: Sextillion is the word with new star discovery ; The census estimate is his lead story, but he gets to the super-Earth news too.
- Daily Mail (UK) Fiona Macrae:Under a septillion suns:The universe hold THREE times more stars than was previously thought ; A “maybe” goes with that hed, if one reads the story’s text. This being a newspaper of a certain nature, there is no surprise that it closes with statistics on how many Britons believe in space aliens.
- USA Today – Dan Vergano: Universe holds billions more stars than previously thought ; Yes, even billions of billions more. For once “billions” is a drastic understatement by many orders of magnitude. One thinks confidently that Vergano, an old hand with a fine sense of proportion, did not write the headline. He gets nicely into the confusion this may sow among theoreticians seeking to explain how galaxies form. And he hints at a problem: If, as supposed, these elliptical galaxies stuffed with red dwarfs are themselves the result of mergers among spirals such as the Milky Way, presumably less populated by red dwarfs, how does the end result end up with more than were in the ingredients?
- NYTimes – Kenneth Chang: How Many Stars? Three Times as Many as We Thought, Report Says ; Nice touch at the end. Chang asks whether we now get three times as many wishes.
- BBC – Pallab Ghosh: ‘Trillions’ of Earths orbit red stars in older galaxies ; This is a little odd. On reading the hed, I thought Ghosh had combined the galaxy-count story with the exoplanet story to infer how many more planets we might surmise are out there. But he does not mention the news on GJ 1214b.
- Science News – Ron Cowen: It’s really full of stars ; The hed is a fine allusion to 2001: A Space Odyssey, and it fits. This really is an oh-my-god moment for some astronomers.
- ditto for Scientific American – Cynthia Graber (podcast): It’s Even More Full of Stars ;
- …. could go on.
Second pic – hi def version, and no, it’s not real data but an artist’s illus of the relative proportion of red dwarfs in our galaxy, and in the giant ellipticals given spectral inspection.
Grist for the Mill: Yale University Press Release;
- Charlie Petit
