Building galaxies

Jul 11, 2011
An optical image of the giant elliptical galaxy NGC 1407 and the large population of globular clusters (small starlike objects) scattered around it. New studies of these globular clusters confirm the theory that the outer regions of this galaxy are younger, and probably the result of interactions with neighboring galaxies. Credit: Hubble Space Telescope

(PhysOrg.com) -- Galaxies frequently collide with one another. Our own Milky Way galaxy, for example, and its nearest giant neighbor, the Andromeda galaxy, are heading towards each other at a rate of about 120 kilometers per second; predictions claim the two will merge together in another four billion years or so.

It is not only the future of our home galaxy that interests scientists. These powerful interactions are thought to help produce stars, feed the massive that sit at the cores of galaxies, and in general influence in fundamental ways the development and evolution of galaxies.

According to theory, the later stages of a galaxy's growth are the ones dominated by sporadic collisions; in the earlier stages a galaxy steadily accumulates material from its surroundings. These early phases should dominate the nature of stars in the older, inner regions of a galaxy, whereas interactions dominate the stars in the outer regions. The two sets of stars are demonstrably different, distinguished by the relative abundances of their elements in the sense that heavier elements signal older, evolved stars.

A galaxy's can provide a measure of a galaxy's element abundances, and how they vary. A globular cluster is a roughly spherical ensemble of stars (as many as several million) that are gravitationally bound together and typically located in the outer regions of . CfA astronomer Jay Strader, together with five colleagues, has examined the family of about 2600 globular clusters around the giant elliptical galaxy NGC1407, which is interacting with its neighbor, NGC1400.

The team reports finding a strong variation in the elemental abundances of the globular clusters, with those closer to the galaxy having more heavier elements. The evidence provides strong confirmation of the overall model in which the inner regions formed earlier, by steady accumulation, whereas the more distant, outer regions, which were involved in more recent interactions, are younger.

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User comments : 10

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Mikeal
5 / 5 (2) Jul 11, 2011
It's comming right for us!
racchole
2 / 5 (4) Jul 11, 2011
Looks like I picked the wrong week to quit sniffin glue.
pres68y
1.3 / 5 (8) Jul 11, 2011
According to the "Big Bang" hypothesis the universe is expanding.
Using that unlikely logic, there is not much chance of collision.
Husky
5 / 5 (3) Jul 12, 2011
expanding at a much vaster scale than gravity linked local groups of galaxies, the distance between us and andromeda is pretty insignificant if we talk about the scales of superclusters and filaments
Deesky
5 / 5 (2) Jul 12, 2011
According to the "Big Bang" hypothesis the universe is expanding.
Using that unlikely logic, there is not much chance of collision.

You should take a course in basic logic and science before making foolish comments on a science website.
omatumr
1.4 / 5 (9) Jul 12, 2011
Building galaxies


Occurs from the exploding galactic core.

Colliding galaxies is another matter.

With kind regards,
Oliver K. Manuel
Former NASA Principal
Investigator for Apollo
LKD
5 / 5 (1) Jul 12, 2011
I am curious how the elder elliptical galaxy is dealing with the collision. If this will create spiral arms with the infusion of matter to start new reactions in the galaxy.
antialias_physorg
4.3 / 5 (6) Jul 12, 2011
Building galaxies
Occurs from the exploding galactic core.


This makes no sense. How can a GALACTIC core be (always) the building block of a galaxy. Chicken and egg?

And funnily - no matter how far we look back - we see no 'exploding galactic cores'.

You should stick to neutron repulsion or whatever your pet theory is called. At least there you obfuscate a lot better that you're not making any sense.
Resonance
4 / 5 (4) Jul 12, 2011
Ya and also apologize to your children you sicko.
jsdarkdestruction
4 / 5 (4) Jul 13, 2011
Building galaxies


Occurs from the exploding galactic core.

Colliding galaxies is another matter.

With kind regards,
Oliver K. Manuel
Former NASA Principal
Investigator for Apollo

Yes oliver, of course. its all a conspiracy against you and everyone else is just lying to keep you from getting credit for your discovery, right? I mean, who needs actual data? you worked for nasa and taught at some university till you got escorted off campua when they found out about those multiple rape and sodomy charges relating to your children. Of course your right, why would anyone ever doubt you? evidence is just a formality, right?
Anyway, decent article, i liked reading it.

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