Collection of nebulae, stars, dust, and other matter that is typically tens or hundreds of thousands of light years in diameter.

Galaxies come in all sorts of different shapes and sizes. Our galaxy, which we call the Milky Way is a spiral galaxy, so named because, suprisingly enough, it looks somewhat like a spiral. IIRC begin cluelessness , our galaxy has 3 spiral arms, each with a particular name - the spiral arm we are in is called the Saggitarius arm. (?)(sp?)

end cluelessness

Galaxies are typically described by their form. Some common types: I used to know a lot more, but it has been years since I was an astronomy nut...sorry :)

Galaxies are organised into groups and superclusters of anywhere from a few to millions of galaxies. Our galaxy's group, the oh-so-originally named Local Group, contains many galaxies, of which ours is the second largest. The largest galaxy in the Local Group is the Andromeda galaxy, which is visible to the naked eye on a good night.

Our galaxy has two smaller galaxies orbiting it: the Small and Large Magellanic Clouds, or LMC and GMC for short. Galaxies are generally thought to have black holes at the center; ours, apparently, is no exception.

One more fact (?): apparently, the arms of a spiral galaxy are not 'really' there. The illusion is caused by 'waves' of star formation which 'ripple' around the galaxy, propelled by supernovae triggering nearby nebulae to contract into new stars. Components of a galaxy do, however, orbit the center - just not at the same speed as the arms.
Recent observational astronomy has shown that most, if not all galaxies contain a super-massive black hole with a mass of millions or even billions of an ordinary star.

Current theory suggests that these black holes did not form later in the evolution of the galaxies, from many stars or black holes accreting together to 'grow' the hole, but rather they were present at the birth of the host galaxy, and are indeed responsible for it's structure.
Actually, the above might be incorrect, the collapsing cloud may be too unstable to for a huge black hole to form. Rather superclusters of stars may form, and collapse to 'medium' sized holes, which then aggregate.. I'd like somebody who knows to let me know!

After the big bang the majority of the universe consisted of hydrogen, as the universe expanded and cooled, small irregularites in the overall density caused 'clouds' of hydrogen to form. Gradually these began to collapse under gravity, forming black holes of collosal size.

As the gas clouds were irregulary shaped, as they collapsed, the black holes they contained were given spin. The black hole continues to suck in more of its surrounding hydrogen, which spirals into the hole, much like water down a plug-hole, feeding and growing as it does so. Due to the rotation of the hole, material in fact builds up in a disc around it. Friction occurs between the molecules of gas in this disc, heating the gas to millions of degrees, emitting radiation at nearly all wavelengths. Perhaps the quasars that we see are merely galaxies at this period in their evolution.

This in turn produces an effect like the solar wind only many orders of magnitude larger, which in fact pushes the outlying hydrogen outwards. The effect is so huge, it's much like an explosion occuring at the center of the proto-galaxy, with shock waves rippling outwards. It thought that these shock waves triggered the first bursts of star formation.

This also provides a mechanism by which quasars operate; the infalling material heats up so much, that it outshines the rest of the galaxy. (Also see Blandford Znajek process for more info...)

Eventually however the infalling material is pushed so far away by the outpouring of radiation, that in no longer falls into the hole, it orbits it. At this point the black hole ceases to grow, (i.e. suck much more material in), the central region darkens, and the rest of the galaxy settles down, to appear much as we see them today.

Galaxy is the literary magazine at Brighton High School, a HS in Brighton, a suburb of Rochester, NY, USA.

The literary magazine holds weekly meetings: Each Sunday, the "staff members" meet at an arbitrary student's house to discuss the submissions (and eat and drink).

At the end of the school year, beautiful, art-laden copies of Galaxy are sold for one dollar at Springfest, BHS's annual outdoor party.

The parallels to E2 are enormous:

And the differences:

Gal"ax*y (?), n.; pl. Galaxies (#). [F. galaxie, L. galaxias, fr. Gr. (sc. circle), fr. , , milk; akin to L. lac. CF. Lacteal.]

1. Astron.

The Milky Way; that luminous tract, or belt, which is seen at night stretching across the heavens, and which is composed of innumerable stars, so distant and blended as to be distinguishable only with the telescope. The term has recently been used for remote clusters of stars.

Nichol.

2.

A splendid assemblage of persons or things.

 

© Webster 1913.

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