How Much Of YW Was Planned From The Beginning? E.g. Did You Know About Bobo When You Were Still Writing

New observations of a ‘dust trap’ around a young star solve long-standing planet formation mystery Astronomers using the new Atacama Large Millimeter/submillimeter Array have imaged a region around a young star where dust particles can grow by clumping together. This is the first time that such a dust trap has been clearly observed and modeled. It solves a long-standing mystery about how dust particles in discs grow to larger sizes so that they can eventually form comets, planets and other rocky bodies.

Astronomers now know that planets around other stars are plentiful. But they do not fully understand how they form and there are many aspects of the formation of comets, planets and other rocky bodies that remain a mystery. However, new observations exploiting the power of ALMA are now answering one of the biggest questions: how do tiny grains of dust in the disc around a young star grow bigger and bigger—to eventually become rubble, and even boulders well beyond a metre in size?

Computer models suggest that dust grains grow when they collide and stick together. However, when these bigger grains collide again at high speed they are often smashed to pieces and sent back to square one. Even when this does not happen, the models show that the larger grains would quickly move inwards because of friction between the dust and gas and fall onto their parent star, leaving no chance that they could grow even further.

Somehow the dust needs a safe haven where the particles can continue growing until they are big enough to survive on their own. Such “dust traps” have been proposed, but there was no observational proof of their existence up to now.

Bottom left image: Artist’s impression of the proposed disk structure of Oph IRS 48. The brown spots represent the large and small grains. The larger grains detected by ALMA are concentrated in the dust trap at the bottom of the image. The blue represents the distribution of carbon monoxide gas. The gap in the disk is shown with the proposed planetary body that is sweeping the area clear and providing the conditions necessary to form the dust trap. Credit: Nienke van der Marel

Nienke van der Marel, a PhD student at Leiden Observatory in the Netherlands, and lead author of the article, was using ALMA along with her co-workers, to study the disc in a system called Oph-IRS 48. They found that the star was circled by a ring of gas with a central hole that was probably created by an unseen planet or companion star. Earlier observations using ESO’s Very Large Telescope had already shown that the small dust particles also formed a similar ring structure. But the new ALMA view of where the larger millimetre-sized dust particles were found was very different!

“At first the shape of the dust in the image came as a complete surprise to us,” says van der Marel. “Instead of the ring we had expected to see, we found a very clear cashew-nut shape! We had to convince ourselves that this feature was real, but the strong signal and sharpness of the ALMA observations left no doubt about the structure. Then we realised what we had found.”

What had been discovered was a region where bigger dust grains were trapped and could grow much larger by colliding and sticking together. This was a dust trap—just what the theorists were looking for.

Bottom right image: ALMA image of the dust trap around Oph IRS 48. The distinctive crescent-shaped feature comes from the accumulation of larger dust grains in the outer regions of the disk. This provides the safe haven dust grains need to grow into larger and larger objects. Credit: ALMA (ESO/NAOJ/NRAO) / Nienke van der Marel

As van der Marel explains: “It’s likely that we are looking at a kind of comet factory as the conditions are right for the particles to grow from millimetre to comet size. The dust is not likely to form full-sized planets at this distance from the star. But in the near future ALMA will be able to observe dust traps closer to their parent stars, where the same mechanisms are at work. Such dust traps really would be the cradles for new-born planets.”

The dust trap forms as bigger dust particles move in the direction of regions of higher pressure. Computer modelling has shown that such a high pressure region can originate from the motions of the gas at the edge of a gas hole—just like the one found in this disc.

“The combination of modelling work and high quality observations of ALMA makes this a unique project”, says Cornelis Dullemond from the Institute for Theoretical Astrophysics in Heidelberg, Germany, who is an expert on dust evolution and disc modelling, and a member of the team. “Around the time that these observations were obtained, we were working on models predicting exactly these kinds of structures: a very lucky coincidence.”

The observations were made while the ALMA array was still being constructed. They made use of the ALMA Band 9 receivers—European-made devices that allow ALMA to create its so far sharpest images.

“These observations show that ALMA is capable of delivering transformational science, even with less than half of the full array in use,” says Ewine van Dishoeck of the Leiden Observatory, who has been a major contributor to the ALMA project for more than 20 years. “The incredible jump in both sensitivity and image sharpness in Band 9 gives us the opportunity to study basic aspects of planet formation in ways that were simply not possible before.”

Since it came up in the chat, the “official”, from Diane Duane herself, pronunciation of ‘dai stiho’.

NASA's Next Giant Leap

Technology drives exploration and we're building on the Apollo program's accomplishments to test and fly transformative, cutting edge technologies today for tomorrow's missions. As we develop and test the new tools of 21st century spaceflight on the human path to Mars, we once again will change the course of history.

The most basic mobile phone is in fact a communications devices that shames all of science fiction, all the wrist radios and handheld communicators. Captain Kirk had to //tune// his fucking communicator and it couldn’t text or take a photo that he could stick a nice Polaroid filter on. Science fiction didn’t see the mobile phone coming. It certainly didn’t see the glowing glass windows many of us carry now, where we make amazing things happen by pointing at it with our fingers like goddamn wizards.

Warren Ellis » How To See The Future (via ultralaser)

#oh my god everything about this article is hitting me where I live     #forsake manufactured normalacy and look at how extraordinary the world is right now     #there are six people living in space and we can /print/ organs and control satilites with apps     #”Voyager 1 is more than 11 billion miles away and it’s run off 64K of computing power and an eight-track tape deck”     #the internet itself is a goddamn miracle in the making in that humanity—vast swathes of otherwise unconnected humanity—gets together     #to watch cat videos and talk about television and laugh at each other’s jokes     #if the world isn’t thrilling you YOU ARE NOT PAYING ATTENTION     #god     #I’m all     #yeah  (via notbecauseofvictories)

Don’t forget the fact that two robots on another planet have Twitter accounts and people here on Earth can follow them and their discoveries. Astronaut Col. Chris Hadfield—my favorite Canadian—has a Tumblr and posted images from space so that we could see what he was seeing. We can watch videos of galaxies merging on YouTube. And we are making so many scientific discoveries that there’s actually a blog called World Science Festival that details discoveries made each WEEK.

Yes, the world is still fucked up in any number of ways, and the problems need to be fixed. But the world’s also amazing.

(via gehayi)

http://jenesaispourquoi.tumblr.com/post/90776856846/someone-pointed-out-to-me-awhile-ago-that-in-syw

Someone pointed out to me awhile ago that in SYW… they need all sorts of special materials to do their spells, and then later they just need words. Does anyone remember the explanation for that shift? i’m looking back through DW because i figure that’s where it would be? Or maybe in HW or AWAb?

…

guys

guys

less than three months til the games wizard play release

Galactic Poetry

The downfall of living in an urban center, is that all we get to see during the night are blankets of cloud (possibly smog), and if we’re lucky, a few stars. What artist Sanjeev Sivarulrasa is trying to show in his work, Night Light, is what we are missing out on; a magical world, swimming through space, with galaxies and nebulae bejeweling the cosmos.

It is visual poetry.

The artist uses astrophotography to capture the various forms and colours of the stars and planets outside of an observatory setting. According to journalist Becky Rynor, it is as if he is capturing the great masterpieces that our ancestors would see; a natural art. Space does not have to be sacred scientific ground; it can also be merely another aesthetic aspect of our lives, that inspires people to think about the greater world around us. The simple observer plays as big of a role, as the great scientist. When this right to observe is taken away from us, via artificial city lights, we have to make the effort to go to the sources such as countryside’s, forests, lakes, and mountains. We must go to the nature, to connect back to ancient ideas of aesthetic beauty, and renew the senses. Sanjeev’s astrophotographs are to be seen as meditative, bringing awareness to our daily surroundings, and that sometimes, we need to take a step back, and see the bigger picture.

Night Light is currently exhibited at Karsh-Masson Gallery, until the 5th of May, 2013, and there will be an artist talk on the 24th of March, 2013 -Anna Paluch

My boyfriend would like to know what a Godiva chocolate bar would run on the galactic market? I wasn't sure, given what you had said about Hershey bars, since I don't have a frame of reference.

Well, obviously there’s a lot of room for subjectivity about this. Some collectors (Galactic or otherwise) will feel differently. But generally speaking, I suspect the collectors’ opinions will roughly match mine.

Ranking gets complicated because old chocolate companies and brands keep getting bought by bigger companies / conglomerates, and the brands and the quality of their chocolate tend to suffer as a result. By and large, though, the best chocolate tends to be made by companies that do so-called “bean-to-bar” production. The longer the history of this, the better. In general, artisanal chocolate, especially single estate/single bean chocolate, and organic and free-trade chocolates, will also be preferred by the discerning intergalactic collector.

Ranking chocolate from worst to best: (and yes, for those who’re wondering, I’ve eaten all of these, normally on their home turf):

North American chocolate: Almost routinely no better than poor-to-middlin’ quality: the bigger the producer, routinely, the worse, as they keep trying to do it cheaply and good chocolate can’t be done cheaply. It’s too energy-intensive, especially as regards the time and energy required in the conching process that’s absolutely key in giving merely okay chocolate a chance to become great. Hershey’s is the worst of the lot because they’re purposely catering to that spoiled-milk taste that’s become traditional for them. …The exceptions to the poor-to-meh quality rule are invariably smaller producers like Ghirardelli. Meanwhile it should probably be no surprise that when the Lexington Avenue Local worldgate was resited following the refurbishment of Grand Central Terminal, it wound up behind Li-Lac Chocolate’s satellite branch in the food hall. One might suspect Carmela’s straightforward hand in this.

European-based chocolate generally: Significantly better. …Subdividing into:

British Isles chocolate: Pretty good most of the time. Many small classic brands (Fry’s, Rowntree) were subsumed into bigger British chocolate companies over time, with only slow degradation of general quality. Cadburys is probably at the top of the heap, despite what’s happened to the Creme Egg over the years. (mutter)  …And naturally I would be remiss in not mentioning, on the Irish side, Lir, Lily O’Brien’s, and Butlers. (When we go to visit friends in Switzerland, we bring them Lir.) Additionally, there are people who are vocal about their claims that Irish Cadburys is better than British Cadburys, due to local/regional differences in the mix. Myself, I refuse to get mixed up in local chocosectarian stuff. Life’s too short.

Italian and French chocolate: Perugina, Valrhona (as in “I’d rather be in Valrhona than Valhalla”), Callebaut, Agostoni, Amedei, and Bernachon stand out. There are many more smaller makers in the region worth looking out for: check this list for some.

Belgian chocolate: Almost always really good, even at the mass-produced end (Guylian); sometimes terrific (Leonidas) or more than terrific (Neuhaus, Galler, Dumon). This is where Godiva fits in. (I first had it when its initial New York store opened in 1972: it was far better then than it is now. Then again, having been owned by Campbell’s Soup can’t have been good for them.)

Swiss chocolate: Probably the best: certainly routinely seen as such (and collectors will be aware of the implications of this). Again, the smaller the producer the better. The great/old houses like Lindt and Sprüngli are being given a run for their money by newer competitors like Teuscher and Läderach (attn @petermorwood: Stengli!!).

…I’ll complete this later as I just splashed some tea on my keyboard and I seem to have a membrane problem. (sigh)

(Resuming after prying off all the keycaps and cleaning out what could have been the start of a small tool-using civilization if it was let go much longer:)

So anyway, we were attempting to tease out how Godiva would do on the Galactic chocolate collectors’ market.

It’s all so relative. But there are a number of different factors in play, so better to take them one by one.

(a) Provenance / authenticity. Real Chocolate From Earth (SM*) still has to be specified, these days, in some parts of the Galaxy: as with any unique collectible, there are always counterfeits out there. But none of them work perfectly, not even those produced by atom-by-atom matter duplication. There’s just something about genuine Earth-grown cocoa beans that cannot be duplicated. (If we pulled Dr. McCoy into this discussion he’d simply snort and say, “It’s soul. Why d’y’think I hate that damn transporter so much?”) And the bad fakes…  (shudder) Well. You know the correlation between flavors (and everything else) of chocolate versus carob? The comparison between real chocolate and bad fake chocolate is like that. But generally worse.

(b) Reputation and/or scarcity on planet of origin. Godiva is not hard to find, but its lower-end-of-high-midrange reputation would affect the going price. Many artisanals or single-estates would bring in much, much more on the collectors’ market. But Godiva still would not be cheap.

© Freshness and state of packaging. Fresh and perfectly packaged Godiva obtained before the first of the large corporate acquisitions via timeslide would bring a way higher price than the stuff available on the high street right now.

(d) The present state of cocoa futures. Believe me when I tell you that none of Earth’s financial markets are so closely scrutinized off-planet as the cocoa futures market. A serious ripple in the world’s cocoa production figures can send shockwaves through the collectibles and personal-chemical-enhancements markets galaxy wide (in the latter case, for those species who use chocolate as an aphrodisiac, mood-altering drug or hallucinogen). If anything was going to bring on the classic aliens-arrive-from-space-to-save-Earth-from-itself scenario, it would be news that we had fucked up our climate so totally that the cocoa bean was going to die out. The intervention wouldn’t happen because of any particular altruism, oh dear me no… but because with the death of Earth’s cocoa, many extremely currency-sensitive aspects of the Galactic economy would take a hit that would make the Earth’s recent nearly-worldwide-bank meltdown look like an insolvency involving a kid’s lemonade stand. 

Anyway, the state of the market pushes the day to day price of collectible chocolate up and down in unpredictable but interesting ways, and the smart investor keeps its ears (or legs or abdomen or whatever it listens with) to the ground to stay informed about what’s going on in Earth’s so-called “soft commodities” markets.

(e) Preparation. How much actual chocolate is in the confectionery and how has it been prepared? Plain solid chocolate is always preferable for collectors’ purposes. (The two-pound solid chocolate ingots that Kron Chocolatier in Manhattan used to sell back in the day would have been seen as very choice.) Dark chocolate is always preferable to milk: the milk is seen as an adulteration, as 18K gold is seen as inferior to 24K by precious-metal collectors. Some additives, if psychoactive or otherwise seen as valuable on their own, are viewed as positive (see the chocolate business with Nita and Kit at the Crossings here.)

(f) Demand. Is the product hot right now? Has some buzz about it in the collectors’ networks kicked the price up for some reason? 

…And there are other factors, but you get the general idea. So if you were offering a Godiva bar on the open market, say one of these, depending on where you planned to do your shopping afterwards you could probably exchange it for enough currency in one of the smaller spacefaring cultures that’s chocolate-using in one of the valuable ways (meaning as a recreational chemical) to get yourself a small private island on some planet where the climate suited you. Or a nice little space yacht. (Nothing really huge. After all, you need to pay for crew services too, and berthing, and… Never mind.)

Hope this helps. :)

*Service mark is the property of Gaia Protectorate CRLLC: for more information see here.

Coldest Star Found—No Hotter Than Fresh Coffee

According to a new study, a star discovered 75 light-years away is no warmer than a freshly brewed cup of coffee.

Dubbed CFBDSIR 1458 10b, the star is what’s called a brown dwarf. These oddball objects are often called failed stars, because they have starlike heat and chemical properties but don’t have enough mass for the crush of gravity to ignite nuclear fusion at their cores.

With surface temperatures hovering around 206 degrees F (97 degrees C), the newfound star is the coldest brown dwarf seen to date.

Keep reading.