Most elliptical galaxies are 'like spirals'

Jun 20, 2011
Most elliptical galaxies are 'like spirals'
Maps of the observed velocity of the stars in the Atlas3D survey. Red/blue colours indicate stars moving away/towards us respectively. Fast rotating and disk-like galaxies are characterised by two large and symmetric red/blue peaks at the two sides of the centre and constitute the majority of the sample.

(PhysOrg.com) -- The majority of 'elliptical' galaxies are not spherical but disc-shaped, resembling spiral galaxies such as our own Milky Way with the gas and dust removed, new observations suggest.

The results come from Atlas3D, a survey of all 260 early-type ('elliptical' and 'lenticular') galaxies in a well-defined volume of the . Atlas3D shows a much closer link between ‘elliptical’ galaxies and spiral galaxies than previously thought. The findings are likely to change our ideas of how galaxies form and see astronomy text-books rewritten.

A report of the research, by the international Atlas3D team, is published in an upcoming issue of Monthly Notices of the Royal Astronomical Society.

‘Because we rely on optical images, up until now it has been very difficult to separate discs of stars seen face-on from rounder, spherical balls of stars seen edge-on,’ said Dr Michele Cappellari of Oxford University, a Royal Society Research Fellow who is the UK lead of the Atlas3D project. ‘But because stars in a thin disc rotate much faster than those in a spheroid, obtaining maps of stellar motions for all elliptical galaxies in the sample, we have shown that out of these 66% are disc-like.’

The findings suggest that the idea that galaxies can be clearly separated into two different ‘families’, spiral galaxies and elliptical galaxies, reflecting two distinct paths to galaxy formation, is inaccurate.

This ‘two families’ approach was famously visualised in Edwin Hubble’s ‘tuning fork’ diagram of 1936 in which elliptical nebulae, which consist of more spherical groups of stars, split off into two prongs of spiral galaxies (with and without bars). The Atlas3D results suggest that this tuning fork should be replaced with a ‘comb-like’ diagram where elliptical galaxies are parallel to spirals and linked to them along the teeth of the comb while only a few true ellipticals are separated into the handle.

‘According to our survey only a small fraction of , the ‘slow rotators’, are genuine spheroids. It reveals a strong family resemblance between elliptical and spiral galaxies once we can adjust for whether we are seeing them face-on or from the side,’ said Dr Cappellari. ‘This close relationship will need to be considered in any future models of how galaxies form. It’s an exciting moment, after four years of work in the project, we have the final piece of the puzzle which enables us to say that text-books used to teach astronomy for over 70 years now need to be revised.’

The team, led by Dr Michele Cappellari of Oxford University’s Department of Physics, Eric Emsellem, Davor Krajnovic (ESO, Germany) and Richard McDermid (Gemini, USA), compiled their maps of stellar motions from 40 nights of observations using the SAURON integral-field spectrograph at the 4.2-m William Hershel Telescope on the Canary Islands.

A report of the research, entitled ‘The Atlas3D project - VII. A new look at the morphology of nearby galaxies: the kinematic morphology-density relation’ is to be published in an upcoming issue of Monthly Notices of the Royal Astronomical Society. Lead author Dr Michele Cappellari was supported through a Royal Society Research Fellowship.

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omatumr
1.4 / 5 (15) Jun 20, 2011
The key question concerns the event that produced the disk.

Was it by accretion of intergalactic material, as commonly reported in textbooks?

Was it neutron-repulsion induced fragmentation of a central object, as we suggest?

"Neutron Repulsion", The APEIRON Journal, in press, 19 pages (2011):

http://arxiv.org/...2.1499v1

With kind regards,
Oliver K. Manuel
hooloovoo
4.3 / 5 (12) Jun 20, 2011
Is neutron repulsion the cause of everything that ever happens in your universe?
yyz
5 / 5 (3) Jun 20, 2011
"The Atlas3D results suggest that this tuning fork should be replaced with a comb-like diagram where elliptical galaxies are parallel to spirals and linked to them along the teeth of the comb while only a few true ellipticals are separated into the handle."

Fig. 1 of their paper presents their 'comb-like' diagram using galaxies selected from this study: http://arxiv.org/...45v1.pdf

The authors note that this new diagram is similar to a classification scheme first proposed by Sidney van den Bergh whereby S0 galaxies are seen to mirror the spiral sequence of Sa-Sb-Sc and introduces a class of intermediate 'anemic' spirals(Aa-Ab-Ac): http://articles.a...ype=.pdf

The current paper also notes that their derived relation breaks down when applied to dense galaxy clusters, suggesting a different formation mechanism.
Tuxford
2.1 / 5 (7) Jun 20, 2011
This too is in agreement with LaViolette's inside-out growth model of galaxy formation. Spirals grow into giant ellipticals, not the reverse. Giant ellipticals are the final stage of growth. Recent news that many if not all early galaxies are growing in tandem with their black hole cores therein also supports this view. Stars moving radially away from galactic center in our local universe is another clue about galaxy formation. And the massive outflows (and outbursts) from various galaxy cores is still another clue.
MarkyMark
not rated yet Jun 21, 2011
Is neutron repulsion the cause of everything that ever happens in your universe?

Heh it seems so, still tho i love some of this persons posts as they are pretty funny. Also is it true what i hear about him and his caring nature towards children?
rawa1
3 / 5 (2) Jun 21, 2011
This observation supports Steady-state universe, rather then Big Bang Universe. In Big Bang universe it's expectable, the old galaxies will differ from these young ones, because the were formed in different epochs of Universe formation. In Steady-state universe the will not differ significantly from mid-age galaxies. I admit, this link is weak and it can be interpreted many other ways, but it's not the only one in the game. The large inhomogeneity of Universe observed recently at large scales supports the Steady-state model in the same way, like the recent findings of mature galaxies inside of Hubble's deep field.

Each of these links is rather weak by itself, but when considered together, then they're giving rather convincing view of Universe character and evolution. It's example of pluralistic thinking, which provides answers even under situation, when explanation based on deterministic connections is unavailable.
Deesky
5 / 5 (1) Jun 21, 2011
Also is it true what i hear about him and his caring nature towards children?

Yes, it is.
Tuxford
1.7 / 5 (6) Jun 21, 2011
That the old stars are moving in every direction like bee's in giant ellipticals, further hints that ellipticals are just the final phase of galaxy evolution. Spirals grow into giant ellipticals. The stars grow old. The core grows massive, and generates new matter at an ever increasing rate. There is no mystery if one observes the ejections of new gas from the cores of many galaxies. If it walks like a duck...

http://www.physor...ies.html
MarkyMark
not rated yet Jun 22, 2011
Also is it true what i hear about him and his caring nature towards children?

Yes, it is.

Thats disgusting them how he can even show his face in here is a mystery to me!
omatumr
1 / 5 (6) Jun 22, 2011
Is neutron repulsion the cause of everything that ever happens in your universe?


No. Two opposing forces compete and sustain our dynamic universe:

a.) The gravitational force of attraction.
b.) The repulsive force between neutrons.

These two forces favor different forms of the one fundamental particle that comprises the entire cosmos and every atom in it:

Neutron <=> Hydrogen Atom
Nuclear <=> Atomic
Small <=> Large

The volume occupied by an interstellar H-atom, V(H-atom), is much, much larger than the volume occupied by a neutron, V(neutron), in the core of a star.

V(neutron)/V(H-atom) = 10^23
V(neutron)/V(H-atom) = 100,000,000,000,000,000,000,000

That is why our infinite, ageless universe oscillates between cycles of

Compression <=> Expansion

"Is the Universe Expanding?", The Journal of Cosmology 13, 4187-4190 (2011):

http://journalofc...102.html

That seems to fit observations that we have now.

Oliver K. Manuel
Gawad
3 / 5 (2) Jun 22, 2011
Oh gawd, I may be about half made of neutrons, but I think I'm coming down with a severe case of neutron revulsion!
Javinator
not rated yet Jun 22, 2011
The volume occupied by an interstellar H-atom, V(H-atom), is much, much larger than the volume occupied by a neutron, V(neutron), in the core of a star.

That is why our infinite, ageless universe oscillates between cycles of

Compression <=> Expansion


I'm confused. Are you suggesting that, if a neutron decays into a hydrogen atom and takes up more volume, that the universe expands because of it? What is it pushing on? Space?

I'm just thinking of say... water in an infinitely expanding balloon. If the water in the balloon were suddenly turned to steam, the balloon would expand and increase in volume as a result of the pressure generated. But this happens because the balloon and the steam can physically interact.

Are you suggesting that this increase in volume (which is really just an orbiting electron... the size of a proton is very similar to that of a neutron) somehow physically interacts with the fabric of space to cause universal expansion and collapse?
Javinator
not rated yet Jun 22, 2011
This would suggest to me that the "space" between the electron and the proton didn't exist before the decay and that these decays are actually creating "space" (although I'm aware the electron doesn't "orbit" but exists somewhere within the 1s orbital).
omatumr
1 / 5 (3) Jun 22, 2011
My advice: Read the paper.

Than, be still and contemplate on the matter for a few days.

Our brains process information sometimes when we aren't seeking answers.

MarkyMark
5 / 5 (5) Jun 23, 2011
My advice: Read the paper.

Than, be still and contemplate on the matter for a few days.

Our brains process information sometimes when we aren't seeking answers.


Or you could try and answer questions rather than dodge them. Tho as your 'theory' is just a load of hot air i am not to suprised that you dont give direct answers to questions.