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Speed Found to be Key to Galaxy Formation

CowboyNeal posted more than 7 years ago | from the not-just-a-good-idea dept.

Space 61

QuantumCrypto writes "The All-wavelength Extended Groth strip International Survey (AEGIS), a collaborative effort involving nearly 100 scientists in half a dozen countries, revealed a new principle in the formation of all galaxies, from disk-like spirals, cloud-like ellipticals, and just irregulars. In essence the morphology of the galaxies depends on total mass involved and the internal speed it generates. 'By defining a new speed indicator, their analysis has managed to make sense out of very chaotic-looking objects,' said Sandra Faber, professor of astronomy and astrophysics at the University of California, Santa Cruz."

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+1 submerged galaxy detection (1)

snotclot (836055) | more than 7 years ago | (#18286582)

AEGIS also reported that having their system in a particular galaxy offered +! radius detection of submerged galaxies.

/ok that was horrible
//back to work

Re:+1 submerged galaxy detection (5, Funny)

Seumas (6865) | more than 7 years ago | (#18286596)

Speed Found to be Key to Galaxy Formation

And they said drugs are bad!

Re:+1 submerged galaxy detection (0)

Anonymous Coward | more than 7 years ago | (#18286716)

They are.

Re:+1 submerged galaxy detection (5, Funny)

smaddox (928261) | more than 7 years ago | (#18286794)

This side effect of speed has been known for ages! What rock have these 100 scientists been hiding under?

Hell, first time I did speed, I formed at least 5 new galaxies! Then, I scrubbed them so hard with the galactic sponge that they disappeared completely. Those quasars can be a real pain to get out of your multi-dimensional trousers, though. They always leave behind a bit of redshift.

Re:+1 submerged galaxy detection (0, Offtopic)

Terminus32 (968892) | more than 7 years ago | (#18287100)

Yay for Amphetamines! Except the comedown (or 'Big Crunch') is pretty horrid...

Re:+1 submerged galaxy detection (-1, Offtopic)

Anonymous Coward | more than 7 years ago | (#18287800)

Replying to unrelated first post. Whore.

Re:+1 submerged galaxy detection (1)

Hoi Polloi (522990) | more than 7 years ago | (#18289158)

Are they sure it was Speed [wikipedia.org] and not Racer-X [wikipedia.org] ?

Re:+1 submerged galaxy detection (1)

ensiferius (999312) | more than 7 years ago | (#18295714)

If you had to stay up for 6 days straight working on a project what would you do?

You know that it was just edited out:

"On the second day at about 6 in the morning, God created speed. And God saw that it was the good pharmacutical grade. And he shouted unto the shouted unto the waters, 'Woo Hoo!!!' "

it's a matter of perpective... on the matter (3, Funny)

User 956 (568564) | more than 7 years ago | (#18286604)

In essence the morphology of the galaxies depends on total mass involved and the internal speed it generates.

Yeah, well, it all results in the eventual heat death of the universe, so what's the point really?

Re:it's a matter of perpective... on the matter (1)

cyclop (780354) | more than 7 years ago | (#18287082)

(God speaks): Yeah, at first I thought my own Universe was funny, but now I found eternity is best wasted playing WoW than forming boring galaxies.

(God replaces universe with WoW world.)

Re:it's a matter of perpective... on the matter (3, Funny)

BakaHoushi (786009) | more than 7 years ago | (#18287338)

This DOES explain a lot of the universes problems.

*God creates the universe*
Well, time for a little R&R... guess I'll try that WoW for a little while... The world will be fine...
*Time passes*
WHOO! Level 70! Finally!
*God looks down on the modern world*
OH SHI--

Well duh (1)

theomgfactor (1073566) | more than 7 years ago | (#18286670)

A lot of cosmology seems like common sense. All that "Hawking stuff" I found interesting that the first time I read about it was like a big Ok..and.. I could have told you that (except the black hole radiation part.. that's pretty good stuff). I could have told someone this while bs'ing over a beer in a bar while just joking around on crazy topics. More density = More gravity = More pull = Faster spin = Faster sorting = Faster final formation. Ok so you've got me on making the equation part, that's what undergrads are for.. wait a second I'd be and undergrad had I taken that field of study...

Re:Well duh (1)

TapeCutter (624760) | more than 7 years ago | (#18287918)

"A lot of cosmology seems like common sense.....I could have told someone this while bs'ing over a beer in a bar while just joking around on crazy topics."

Yes, using the properties of galaxies to infer the early state of the primordial quantum flux of a dimentionless quantum dot that exploded into nothing to create everthing and everywhen will be a hot topic in bars tonight. /sarcasm

Re:Well duh (1)

wanerious (712877) | more than 7 years ago | (#18288612)

Wait. Let me guess. You're an engineer.

Re:Well duh (1)

Gilmoure (18428) | more than 7 years ago | (#18289536)

Naw, he's a plumber.

Frdist psot (-1, Redundant)

Anonymous Coward | more than 7 years ago | (#18286674)

worthwhile. So I and Michael Smith the numbe_rs. The bEen the best,

Age of Empire 2 (0, Offtopic)

Verunks (1000826) | more than 7 years ago | (#18286714)

that's why the cheat to build constructions fast was called aegis?

Re:Age of Empire 2 (-1, Offtopic)

Dersaidin (954402) | more than 7 years ago | (#18286762)

I believe it also built units fast.

Speed? (1)

kongit (758125) | more than 7 years ago | (#18286728)

So if speed is the key to the formation of galaxies, where does weed fit in? Is it the key to the meaning of life? Maybe drugs are the keys to vast questions involving the universe, life, and everything else.

Reminds me of... (0)

Anonymous Coward | more than 7 years ago | (#18286732)

The hole formed in coffee when rapidly stirred... mmmmm, coffee.....

Speed is Key, eh? (-1, Redundant)

Tablizer (95088) | more than 7 years ago | (#18286764)

Speed Found to be Key to Galaxy Formation...By defining a new speed indicator, their analysis has managed to make sense out of very chaotic-looking objects,

So you are saying if you take enough speed, then a sad chaotic life makes sense? You said the same about extacy, but it didn't work. It just made me a rambling slashdotter.
               

Simulations (3, Interesting)

Tablizer (95088) | more than 7 years ago | (#18286786)

It would be interesting to see some simulations and animations of rotating spiral galaxies. We could never see that with actual galaxies because they move too slow from our perspective. A simulation will both test to see how accurate their models fit the real thing, and allow us to study how rotation works and spiral arms keep from winding "tighter", as it would otherwise seam. Maybe they could hilight a few reference stars so we can see how they move relative to the spiral arms. As an amature space artist, the movement of the arms relative to stars is a curious wonder that I cannot really visualize yet.
               

Re:Simulations (1)

plasmacutter (901737) | more than 7 years ago | (#18287288)

would they not have to model every star (or at least make an effort to properly model as many individual massive objects as possible) in order to make an accurate model?

if you simplify it you will not learn anything.. if you assume for the sake of simplification an "evenly consistent galactic medium" then youre going to have problems imho.

Re:Simulations (1)

dosquatch (924618) | more than 7 years ago | (#18288040)

would they not have to model every star (or at least make an effort to properly model as many individual massive objects as possible) in order to make an accurate model?

Nah, it should be possible with a variation of particle physics.

In fact, I'm going to be surprised if the behavior doesn't turn out to be fractal-ish in nature. Swirling gasses beget swirling particles beget planets swirling around a star swirling around a galaxy swirling around a megagalaxy swirling about, swirling about.

Swirling, swirling, swirling. Soooo pretty.

Aww, fuck, this coffee is not nearly strong enough... <swirl, swirl>

Re:Simulations (2, Informative)

mdsolar (1045926) | more than 7 years ago | (#18287798)

I know Josh Barnes has produced some vidio of spirals rotating but I have not found it. Here are some more exciting merger simulation: http://www.ifa.hawaii.edu/~barnes/pressrel/mice/vi d301_04.mpg [hawaii.edu] and http://www.ifa.hawaii.edu/~barnes/pressrel/mice/v0 211d3.mpg [hawaii.edu] found at http://www.ifa.hawaii.edu/~barnes/research/interac tion_models/mice/index.html#modeling [hawaii.edu] . Models which concentrate on just rotation tend to be just two dimensional to save on computing. The are used to study secular evolution which could also lead from the Tully-Fisher to the Faber-Jackson relation.
--
Fun with the Sun: http://mdsolar.blogspot.com/2007/01/slashdot-users -selling-solar.html [blogspot.com]

Re:Simulations (1)

Gilmoure (18428) | more than 7 years ago | (#18289580)

If you took a video camera and pointed it at a distant spiral galaxy and then moved in real fast, you could get a video of it's formation, in reverse. You could then submit it to Funny Galaxy Videos show or sumt'ing.

Re:Simulations (1)

cbacba (944071) | more than 7 years ago | (#18316361)

Inside an arm, different objects can have relatively different speeds along the direction of the arm rotation. Also, objects can bob up and down as they go around. Different speeds can be achieved by slight variations and by the changes in gravitational attraction. The arm has got to move at the average speed and it's components generally have to move at this same velocity as it rotates - but some components may be ejected out of the arm. Essentially, each object in the arm is in orbit around the core but is also subject to influence from other arm objects.

Astronomers and amateur astronomers usually think in two dimensions as the problem is finding particular objects in the sky. It's all direction. Distance is not something that can be measured directly outside our immediate area where the parallax of stars from the earth's orbit position changes can be used to determine it. Beyond that, it's inferring from other things like cephid variables or even type 1a supernovae brightness (assumptions). There are quite a few objects that are fairly commonly observed that we don't truly know exactly how far they really are.

One simulation program that has attempted to break this mold is Whereis M13. It used to be shareware but it may be a low cost item now. It will show you where various objects are located in our galaxy. Unfortunately, I don't think it can vary in time.

http://www.thinkastronomy.com/M13/index.html [thinkastronomy.com]

Even the planetarium programs which offer tremendously wide time variations of thousands of years do not offer views of millions of years and probably don't offer a 3 d look at the galaxy even though they may offer a 3-d look at the solar system. Some of the problem may be the accuracy of our numbers on the relative motions may not be good enough to take us back to the skies of the dinosaurs when we were on the other side of the galaxy.

Speed Found to be Key to Galaxy Formation (1)

chowdy (992689) | more than 7 years ago | (#18286800)

What can't speed do?

Okay, that's it. (2, Funny)

mikkelm (1000451) | more than 7 years ago | (#18286814)

I'm hereby announcing the creation of DISTASTEFUL. The organisation against the proDIgal, unnecesSarily conTrived and unnaturAlly nonsenSical abbreviaTion of projEcts and Federally fUnded estabLishments.

Re:Okay, that's it. (0)

Anonymous Coward | more than 7 years ago | (#18288564)

That would be OAPUCUNAPFFE ... Oh! IGI (I get it!)

Speed found........ (-1, Offtopic)

Anonymous Coward | more than 7 years ago | (#18286820)

I've heard of drugs doing interesting things, but this is ridiculous!

I, for one, welcome etc etc (-1)

unitron (5733) | more than 7 years ago | (#18286846)

All hail our new galactic overlord, Groth.

But seriously, am I the only one who thought at first that someone had misspelled "growth"?

Of quantum fluxuations and galactic seeds (3, Insightful)

ArcSecond (534786) | more than 7 years ago | (#18286862)

According to Faber, the relation described in this study may reflect processes that began in the first fraction of a nanosecond after the Big Bang. "Galaxies began life as quantum fluctuations--tiny density fluctuations that created the seeds for the later coagulation of structure in the universe. When gravity took over, those seeds made galaxies, and we think that process is reflected in the Tully-Fisher relation," she said.

I found this part really interesting. I know it is something pointed to already by fluctuations in the Cosmic Background Radiation, but the though that local variations at the smallest scales determined the structure of galaxies is really something to think on.

Re:Of quantum fluxuations and galactic seeds (1)

anandsr (148302) | more than 7 years ago | (#18286968)

I don't understand how Tully Fisher relation comes about in GR+DM. It can come from MOND on the other hand. I don't understand why the article was totally silent on Dark Matter. Tully Fisher relation is very specific to Spiral galaxies, how did they apply it to other galaxy types without using any underlying theory. What was that theory, if it was not MOND or GR+DM.

Re:Of quantum fluxuations and galactic seeds (1)

EinZweiDrei (955497) | more than 7 years ago | (#18287354)

IDK; IANAP.

Re:Of quantum fluxuations and galactic seeds (0)

osu-neko (2604) | more than 7 years ago | (#18287840)

LOL

Re:Of quantum fluxuations and galactic seeds (1)

radtea (464814) | more than 7 years ago | (#18287830)

I know it is something pointed to already by fluctuations in the Cosmic Background Radiation, but the though that local variations at the smallest scales determined the structure of galaxies is really something to think on.

The claim about the mass/combined-velocity[*] correlation being a reflection of big bang seeding of galaxies is really speculative. The fact that it applies to post-collisional galaxies suggests that the relationship is a product of galactic dynamics, not big bang cosmology. It's not impossible that the fingerprints of the big bang are still on these systems, but given the amount of entropy-creation that has been going on since then it is a little hard to believe that the observed correlation isn't due to the ongoing dynamics rather than the initial conditions.

[*] The combined velocity they are using is sqrt(0.5*v_rot**2 + sigma_gas**2), where v_rot is the mean rotation velocity of the stellar component and sigma_gas is the velocity dispersion of the gas component. This also suggests that the tightness of the correlation is due to galactic dynamics rather than initial conditions.

Taking Tully-Fisher one more step (4, Informative)

TMB (70166) | more than 7 years ago | (#18286966)

For those interested in more details, it looks like the preprint is available at http://arxiv.org/abs/astro-ph/0702643 [arxiv.org] .

Originally TF was just a relationship between rotational speed and luminosity. Since luminosity is some measurement of stellar mass, it was proposed a few years ago that the true physical relationship was not with luminosity but with the total cooled baryonic mass (most of which is in the form of stars in most galaxies). So the Baryonic Tully Fisher relation was proposed, where they substituted the total mass of stars and gas instead of the luminosity. The relationship was tighter, indicating that this is closer to the fundamental relationship.

This work now takes it one more step and uses a more physical measurement for the other variable. Rotational speed of a disk galaxy tells you how deep the potential well is, assuming that all of the motion is in the form of rotation. But if there are also disordered motions, then it's really a combination of the disordered and ordered motion that tell you how deep the potential is. So they've replaced the rotation velocity with a combination of rotational velocity and velocity dispersion - and voila, the relationship is even tighter!

Very nice work.

[TMB]

Re:Taking Tully-Fisher one more step (1)

Bootsy Collins (549938) | more than 7 years ago | (#18287570)

Hey Mr. B, what's the status of actually relating the T-F/F-J (or whatever the unified relation is to be called now) to galaxy formation? It's been 5 1/2 years since I left extragalactic astronomy to become a hermit; but my last memory was that we hadn't gone very far in explaining the slope of the relation. Obviously it's steeper than one expects with a constant mass-to-light ratio and simple gravity (especially the Faber-Jackson relation, if you take stellar velocity dispersion on face value, which I guess this work and Ben's previous work would argue not to do). A mass-dependent (M/L) isn't at all surprising, and simulations of galaxy formation in a cosmological context (e.g. Evrard, Summers and Davis; Hernquist and Katz; etc.) did indeed predict as such -- but not with a slope sufficient to explain the T-F relation. They got close, but not quite there. That's how things stood five and a half years ago; is this no longer true? Do we understand the origin of the relation now?

Re:Taking Tully-Fisher one more step (0)

Anonymous Coward | more than 7 years ago | (#18289350)

You forgot the Crabb-Dymer relation which denotes a slowing down of the regular shock solinoids. If you check the research by Gumble-Sizlak you'll see an A-B demarcation that indicates a constant steady state massive. This all assumes a lack of Muntz based losses.

Of course this all depends on whether it is a month ending in "Y".

Re:Taking Tully-Fisher one more step (1)

TMB (70166) | more than 7 years ago | (#18342491)

My sense is that the mass-dependent mass-to-light ratio that you get in a cosmological context does get you the right slope for the TFR. The zero-point is actually the bigger issue - simulated disk galaxies rotate too fast given their stellar mass. However, this may have finally been resolved by better treatments of how supernova energy feeds back on the surrounding gas - there's some recent work by Fabio Governato and collaborators that looks pretty encouraging (eg. Monthly Notices of the Royal Astronomical Society, 374, 1479).

For early-type galaxies, people usually use the Fundamental Plane rather than Faber-Jackson. The mass-to-light ratio has to vary with mass in a very interesting way to explain the curvature in the Fundamental Plane - it has to be high for low-mass dwarfs, low for L*-ish (ie. Milky Way sized) galaxies, and then high again for massive ellipticals and brightest cluster galaxies (see eg. Zaritsky et al. 2006, Astrophysical Journal, 638, 725). The physics at the high mass end is probably the same as the mass-to-light variation you need to explain the slope of the TFR, while at the low end there seems to be some process that inhibits stars from forming... it could be because most of the gas got heated by reionization, or that all the gas got blown out by supernovae, or it could be that star formation is just very inefficient in low-mass galaxies.

[TMB]

Speed to the rescue (0)

Anonymous Coward | more than 7 years ago | (#18286970)

' By defining a new speed indicator, their analysis has managed to make sense out of very chaotic-looking objects,'

Yes, but will this fancy-pants speed formula help me make sense of my very chaotic-looking tax receipts pile?

2nd law of thermodynamics? (0)

Anonymous Coward | more than 7 years ago | (#18287542)

"By defining a new speed indicator, their analysis has managed to make sense out of very chaotic-looking objects"
Just so we're all clear on this, this is a way to "understand" the chaos, not a proof that chaos moves toward order.

Re:2nd law of thermodynamics? (1)

Lord Lemur (993283) | more than 7 years ago | (#18290154)

Actully since the area is cooling I beleive the process is still entropic. This is because it is giving a larger amount of disorganization (to the vaccum around it) then the order of its new state has gained in order. Thus for the Universe the 2nd law is upheld. Locally = more order, closed system = less order.

Like why we can only make memories in the positive time direction.

Disambiguation needed (1)

cabinetsoft (923481) | more than 7 years ago | (#18287568)

"Speed" like the last one here [wikipedia.org] .

I bet that's the cause for a lot of things! /p?

Re:Disambiguation needed (1)

cabinetsoft (923481) | more than 7 years ago | (#18287586)

NO! It's not causing my bad typing too!

Attention Shoppers (1)

Fear the Clam (230933) | more than 7 years ago | (#18287614)

Irregular galaxies are 80% off in our clearance section.

Number of Turns of the Galaxy (2, Interesting)

vbwyrde (1047816) | more than 7 years ago | (#18287708)

I am to understand that our Galaxy rotates on its axis once ever 250 million years or so. If that is right, and the universe is 13 or 14 billion years old, then it would seem that we get this: age of Universe = 13,000,000,000 Years for one rotation of galaxy = 250,000,000 Total Rotations = age / rotation 52 Total Rotations since Universe began? First, is that about right? Second, if that is right then my question is how do galaxies obtain their distinctive shapes after such few rotations? I ask because the ratio of turns to shapes (especially in the case of bar galaxies, and other sharply defined shapes) seems counter intuitive to me.

Re:Number of Turns of the Galaxy (2, Informative)

Anonymous Coward | more than 7 years ago | (#18288834)

That's because the spiral is not caused by the rotation of the galaxy. It's caused by a (more slowly rotating) standing wave in spiral form in the disc. When the wave passes the matter in the disc, new bright young stars are formed and that's what you see.
This was discovered in the 60's I believe.

Tino Meinen

Re:Number of Turns of the Galaxy (1)

mdsolar (1045926) | more than 7 years ago | (#18290562)

It's about right, the Milky Way may have formed as a disk more recently. One way to think about it is that the Sun has been around about 15 times since it formed for a motion of 200 km/s. A way to think about the morphologies of galaxies is to consider that stars form in response to the global potential. This is a hand wave, but you can see how it would not require a lot of mixing to get a fairly smooth distribution of stars. Bars may well be large-scale dynamical instabilities so that their shape, in a manner of speaking, happens of itself.
--
Have your roof watch the Sun: http://mdsolar.blogspot.com/2007/01/slashdot-users -selling-solar.html [blogspot.com]

AEGIS (1)

JudgeSlash (823985) | more than 7 years ago | (#18287776)

Bah!

These results are just a blip on the radar.

Speed is the reason... (1)

Ruvim (889012) | more than 7 years ago | (#18287908)

I always knew that we were just figment of the imagination of some dude on drugs...

A REALLY REALLY FAST nothing (1)

brado77 (686260) | more than 7 years ago | (#18288072)

It all makes sense now. If nobody makes nothing go really really really really really fast, then everything results. At last, an explanation built on common sense.

What is time? What is Velocity? What is Energy? (0)

Anonymous Coward | more than 7 years ago | (#18288754)

This is amazing I tell you, truly amazing.

Scientist have developed a theory of the big bang, speed, galaxy formation, age of the universe all with out a theory of time, is time continuous or digital, or energy, 85 % of the energy according to the latest theories if fully unexplained.

The whole issue reminds one of the situation with Newton physics before Einstein.

The only thing that really bothers me about this is obviously this is the source of Global Warming, all the hot air and gases being generated by bull shit.

Re:What is time? What is Velocity? What is Energy? (1)

Lord Lemur (993283) | more than 7 years ago | (#18290386)

Sting Theory, Quantum Theory and Relativity all talk nicely about what energy "is". Energy is a translation of matter into an equal but not identical form. "All matter is but energy converted into a slow vibration." It is my understaning that Relativity and Quantum Theory dictate that all time, distance, mass, ect are all discreate. Ala Plank time, the quanta, and plank mass. I was trying to write out the formula's but the DayQuil is kicking my ass to hard. Mathmatics being an abstraction of reality permits us to ask many questions of this nature. It may at some point be able to prove by law, as opposed to theory, that the universe isn't further subdividable, however at this point it isn't. That is all, have a plesant day. Theories of Time and Quantum Gravity would help resolve these issues I imagine.

What I take from the title.... (1)

Kazrath (822492) | more than 7 years ago | (#18289550)

Speed Found to be Key to Galaxy Formation
So that is why God was up for 6 days and slept on the 7th.

Can derive galactic output for Milky Wway? (1)

mattr (78516) | more than 7 years ago | (#18289608)

IANA Astronomer but would like to know if this chain of logic is possible, given the theory that galaxies that are brighter spin faster.

Measure spin (average speed of local streaming)
Get confirmation of our galactic shape (should be barred spiral) from that
Get brightness based on spin
Calculate total galactic output based on that
Calculate brightness map of Milky Way seen from Earth
Estimate how much matter is obscuring our view (make a dust map)

And finally if it is possible to estimate average output for specific frequencies, to use that as a floor in optical wavelength SETI search.

Speed, huh? (1)

charlesbakerharris (623282) | more than 7 years ago | (#18289878)

Well, I guess that rules out smack, blow, dope, greenies, and roofies as keys to galaxy formation.

I remember (0)

Anonymous Coward | more than 7 years ago | (#18290048)

Once explaining a theory similar to this long ago I think it was 5 or 6 years ago back in community college. Professor wanted me to write a paper on it which I did some of the research for. But, decided I was a business major taking astronomy for fun and was already getting a B in the class so I gave the notes to the professor and moved on. If I could only prove what I understood intuitively I'd have been an astronomy major.

re: Speed Found to be Key to Galaxy Formation (1)

The Mighty Gerkin (1073836) | more than 7 years ago | (#18292214)

http://www.thunderbolts.info/ [thunderbolts.info] for info on galaxy formation, solar physics, and a bunch of other cool astrophysical stuff

Re: Speed Found to be Key to Galaxy Formation (1)

IHateEverybody (75727) | more than 7 years ago | (#18298054)

And by info, you mean long discredited quack theories right? The electric universe theory which the site you linked to is widely dismissed by most physicists. It does however excite these people [fixedearth.com] .
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