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Galactic Pancake Mystery Solved
mOoZik writes "According to the BBC, Astronomers have figured out why a series of small galaxies surrounding the Milky Way are distributed around it in the shape of a pancake. Theorists believed that the eleven dwarf galaxy companions should have a diffuse, spherical arrangement, but a University of Durham team used a supercomputer to show how the galaxies could take the pancake form without challenging cosmological theory."
The evil Egglons attack, wiping out most of breakfast.
Aha, now all that remains is to find a galaxy shaped like a bottle of maple syrup!
Send email from the afterlife! Write your e-will at Dead Man's Switch.
... and more credit ... (and to enhance discussion :) ...
Full article
The Distribution of Satellite Galaxies: The Great Pancake
Noam I Libeskind, Carlos S Frenk, Shaun Cole, John C Helly, Adrian Jenkins, Julio F Navarro and Chris Power
ABSTRACT
The 11 known satellite galaxies within 250 kpc of the Milky Way lie close to a great circle on the sky. We use high resolution N-body simulations of galactic dark matter halos to test if this remarkable property can be understood within the context of the cold dark matter cosmology. We construct halo merger trees from the simulations and use a semianalytic model to follow the formation of satellite galaxies. We find that in all 6 of our simulations, the 11 brightest satellites are indeed distributed along thin, disk-like structures analogous to that traced by the Milky Way's satellites. This is in sharp contrast to the overall distributions of dark matter in the halo and of subhalos within it which, although triaxial, are not highly aspherical. We find that the spatial distribution of satellites is significantly different from that of the most massive subhalos but is similar to that of the subset of subhalos that had the most massive progenitors at earlier times. The elongated disk-like structure delineated by the satellites has its long axis aligned with the major axis of the dark matter halo. We interpret our results as reflecting the preferential infall of satellites along the spines of a few filaments of the cosmic web.
CC.
TaijiQuan (Huang, 5 loosenings)
It's bunnies all the way down?
ClutterMe.com - easiest site creation on the Net. Just click and type.
Our local cluster is a franchise of IHOP (intergalactic house of pancakes).
... researchers are still working on the mystery of the cosmic sausage and eggs, as well as new puzzling information that seems to indicate the presence of a Great White Handkerchief... or maybe it's a napkin?
Dark Syrup explains galactic pancake mystery.
"Look, I don't want any toast, and he doesn't want any toast. In fact, no one around here wants any toast. Not now, not ever. No toast!"
"How 'bout a muffin?"
"Or muffins! Or muffins! We don't like muffins around here! We want no muffins, no toast, noteacakes, no buns, baps, baguettes or bagels, no croissants, no crumpets, no pancakes, no potato cakes and no hot-cross buns and definitely no smegging flapjacks!"
"Aah, so you're a waffle man!"
This sounds a little like planetary formation. What if these 'halos' were really rings, due to some sort of spin in the original setup? Do they have to be a 3-dimensional halo? I am not an astronomer, but it sounds reasonable to me - could someone please explain this?
Quoth the server, "404."
How much of this kind of research does NASA actually do? It seems that they largely put the satellites in place and maintain them, and universities handle the data analysis.
You can never go home again... but I guess you can shop there.
University of Durham http://en.wikipedia.org/wiki/Durham/
Just 'cause it's not in the US...
...on this pancake, Smucker's already has a patent on it.
Rock on RD! Do we expect the film to be any good?
...there *are* certain galaxies that look like oranges. http://www.eso.org/outreach/press-rel/pr-2003/imag es/Phot32/phot-32a-03-normal.jpg
I don't get it.
without challenging cosmological theory
Isn't it supposed to be about challenging current theories?
I've got a slightly more than average knowledge base on cosmology (though maybe not more than your average slashdotter). I've read a few books, but one thing I've never cleared up: Why do galaxies form in flat spirals and pancaks, and not in gravitationally stable spheres? Is there a simple reason I'm missing?
-dave
http://millionnumbers.com/ - own the number of your dreams
NASA is about rockets. This isn't the sort of stuff they do really do. They help supply data to astronomers/cosmologists/physicists who apply to them, and who, largely, are affiliated with universities and are not "kids."
Dr. Feynman at CalTech and Dr. Sagan at Cornell, for instance, who were both rather famously at odds with NASA more often than not.
"Citizens" have always handled the bulk of astronomical research.
Because more often than not NASA is the necessary enemy of astronomers. It is a government agency, run for the government's purposes, complete with a government beauracracy, and only provisionally interested in theoretical science at all.
But they own Hubble.
I might also point out that these "kids" weren't even in America. England has a university or two worth a damn that might object to being catagorized as "random", and four or five smart people in them. Germany, China, Australia, and hell (as it were), even the Vatican have quite capable cosmologists of their own.
NASA isn't the center of the universe.
KFG
NASA doesn't really specialize in science. It specializes in complex engineering feats where outside scientists run the experiments. When the Mars Exploration Rovers landed on Mars, the project was run by JPL engineers, but the science data was evaluated by scientists at various institutions (initially the ones who helped design the science payloads).
NASA gets credit for many scientific discoveries due to the fact that they wouldn't be made without the NASA hardware. But NASA does not employ the scientists who make the discoveries (except in a few odd projects like asteroid impact research).
when's the galaxy due to flip over?
Sadly, this is not some kids at some random college. Durham is a very well respected university in the UK and Prof. Frenk is extremely well known. He is the fifth most cited physical scientist in the UK and the second most cited space scientist in the world. (The Brits really like to rank things ...)
http://star-www.dur.ac.uk/~csf/homepage/cv.ps
I wonder if this has anything to do with the conjectured cosmic griddle, which heats the primordial galactic batter and makes it te golden hue of our stars and sun?
Well, maybe *you've* never heard of the University of Durham, but it's one of the foremost universities in the UK, and the Physics group there is extremely well-respected.
This isn't "some kids doing a group project", this is proper academic research; you may have heard of that...
It's official. Most of you are morons.
It was my understanding that HOW it got to be that shape was never a mystery. The real mystery was who in the hell was holding that huge spatula, and where did they get it in the first place?
"Everything you know is wrong. (And stupid.)"
Moderation Totals: Wrong=2, Stupid=3, Total=5.
You need to remove the trailing / on the link: http://en.wikipedia.org/wiki/Durham
It's official. Most of you are morons.
An elven dwarf galaxy? Now that's just perposterous!
Or maybe it's a tuesday??
try { Signature mysig = new CleverAttempt(); } catch(NonCleverSignatureException e) { postanyway(); }
Yes, but is it perpendicular?
(ducks)
Theorists believed that the eleven dwarf galaxy companions should have a diffuse, spherical arrangement
Sounds like someone's been watching the Lord of the Rings box set a wee bit much.
Please stop stalking me, bro.
A MILKY WAY Galaxy perhaps...?
The most irritating part of being an astronomer must be constantly defending the allocation of millions of dollars of public funds on whatever it is that they do.
A major new theory in regards to the shape and spacing of galaxies; what difference does it make to anyone?
Any bible-thumping corrupt two-bit schmuck of a politician can come up with a reason why the millions of dollars spent on astronomical research would better be directed towards one of his campaign contributers. And there are lots of those politicians nowdays.
So how actually do the astronomers keep all this money flowing their way? I would suspect that astronomy is 80% math and computer programming now instead of primarily star-gazing.
In the past, it wasn't this hard to justify the astronomers. Gods ruled the stars; kings ruled the people by the grace of the gods; astronomers interpreted the movement of the stars to convince the people that the gods still favored the king, and the king saw to it that the astronomers got plenty of money.
Astronomical research was important in navigation and agriculture. When to plant and which direction to steer when out-of-sight of land was critically important. But real extraterrestial knowledge came slowly. It was only four hundred years ago that Westerners realized that the Earth moved around the sun.
Today the most interesting about astronomy isn't theories about objects billions of miles away, it's how astronomers justify spending millions of dollars looking at objects billions of miles away.
Hawking: Your theory of a donut shaped universe is intriguing Homer, I may have to steal it.
Homer: Wow, I can't believe someone I never heard of is hanging out with a guy like me.
concrete5: a cms made for marketing, but strong enough for geeks.
Anyone who's ridden Space Mountain at Disneyland knows of the existance of Space Cookies
Do we expect the film to ever go into production?
Mmmmmmmmmm......
Universalicious
Never play chicken with a passive aggressive.
*ahem*
the spaghetti incident is a guns n roses album.
calvin had a NOODLE incident at school
-mkb
Darth Syrup saves Episode III.
USE HOT GRITS WITH STATUE OF NATALIE PORTMAN (NAKED AND PETRIFIED)
Milky way
Pancakes
Galaxy
What next? Black holes look like blackcurrents?
My last sig was ridiculed
nobody can prove that!
If only I could mod this up.
-mkb
I just ended my Friday lecture on the local group of galaxies. They're the best measure of the frequency of galaxies out there in the universe, since many dwarf ellipitcals (very common in the local group) are difficult or impossible to see at greater distances.
Professor of Astronomy, Author of Spider Star & Star Dragon (Tor)
The key to this idea is that, given a particular set of initial conditions for the perturbations of density after the Big Bang, matter becomes concentrated in long, thin, filamentary structures. When those structures collapse under the influence of gravity, the result is group of galaxies -- in this, one big one and several small ones -- stretched out along the axis of the early filament(s). So, rather than being distributed all around the big galaxy in a spherical cloud, the little galaxies are arranged in a very loose flattened bunch.
Now, all this depends, of course, on the particular distribution of density perturbations in the early universe. All we astronomers can do is pick some particular model and follow it to see how it evolves. I'm not aware of good reasons for requiring any particular distribution from first principles; people just pick reasonable models that are somewhat easy to describe.
Michael Richmond "This is the heart that broke my finger."
mwrsps@rit.edu http://stupendous.rit.edu
Mmm... pancakes...
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
Anyone else notice that their picture of the Milky Way galaxy has 5 arms? If this is coming from the crack team of scientists, I'm a bit suspicious.
The Braying and Neighing of Barnyard Animals Follows.
You are absolutely kidding right? I've studied at Durham, UK (Carlos Frenk was my Astro lecturer), QM, London, and Stanford, US, and they all have their fair share of smart people. Calling Frenk, or indeed any of these guys "kids" is way out of line. Than again, I could just chalk it up as yet another example of American insularity. (Go ahead, mod me flamebait, I just don't take kindly to the "kids" vs. "pro" and "university of whatever" thing - it's rude and naive).
Dan
Does anyone know which supercomputer they used? I am interested to know because I thought that one that was composed of I don't know how many dual G5s was supposed to be used for astronomy research and the like...
...they do guided tours, rent out the names of stars, and get most of their ancilliary equipment donated to them and off the books.
I do wish some of the PHB industrialists funding the pork-barrelling would wake up to the incredible industrial potential of space, and decide that they have to take a risk and get a piece of pie in the sky right now rather than when they die (and they've got a rude shock coming at that point, along the lines of: "Oi! I left you lot with a perfectly good planet, and now look at it!").
Got time? Spend some of it coding or testing
The problem here, is that in all likelyhood a galaxy shouldn't be shaped like a pancake, that is unless someone put it together specifically to look that way.
Argueing there's a logical complex reason why the milky way is a pancake is like arguing there's a complex reason that only 6 cookies remain in the jar, when your mother placed 20 there.
Try as you might, you're not going to convice your mother that you didn't eat 14 (choak) cookies. The explanation is simple enough, and without solid evidence that someone else ate them, or they came into contact with antimatter cookies, your left withthe simple explanation.
False assumptions (ie, all matter "spawned" from one central location) have no more credibilty if you come up with an unbelievable story of how this might have happend. Simplicity rules here, and if we're really going to use the scientific method, we should be looking back at what most likely did happen, not looking for cop-outs to explain poor assumptions and bias.
"And we have seen and do testify that the Father sent the Son to be the Savior of the World"
1 John 4:14
Pipe and a pancake?
Bong and a blintz?
Cigar and a crepe?
our new yummy buttermilk-flavoured overlords!