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Speed Found to be Key to Galaxy Formation
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."
AEGIS also reported that having their system in a particular galaxy offered +! radius detection of submerged galaxies.
/ok that was horrible
//back to work
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?
The theory of relativity doesn't work right in Arkansas.
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...
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.
Table-ized A.I.
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.
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.
I've got a bad attitude and karma to burn. Go ahead. Mod me down.
For those interested in more details, it looks like the preprint is available at http://arxiv.org/abs/astro-ph/0702643.
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.
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"Speed" like the last one here.
I bet that's the cause for a lot of things! /p?
Irregular galaxies are 80% off in our clearance section.
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.
I always knew that we were just figment of the imagination of some dude on drugs...
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.
Well, I guess that rules out smack, blow, dope, greenies, and roofies as keys to galaxy formation.
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.
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.
http://www.thunderbolts.info/ for info on galaxy formation, solar physics, and a bunch of other cool astrophysical stuff
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.
Does this