Starship Asterisk*

owlice wrote:: falls over laughing! :

O, beyond, I'm SO glad I was eating my toast rather than swilling my cuppa joe, or I should have surely needed to issue an RKA (ruined keyboard alert)!! As it is, I have some crumbs to clean up, and there's peanut butter on the wall. Well worth the clean-up effort, that was; thank you very much!!

So if neufer is getting back to his "Neufermation" self, does that mean he is reneufermating? Perhaps he should sell tickets; I think I'd like to see this!

owlice wrote:

Patiently waiting Yogi wrote:Spiral arms are essentially fixed standing waves and stars orbit into the concave side of these arms and come out the convex side of these arms.

So the arms aren't rotating, the galaxy as a whole doesn't rotate? Stars pass through them as they rotate around the galactic center; the composition of the arms change as stars move through them, is that right?

neufer wrote: Well, I couldn't write my own poem for Owlice, so I guess this is the next best thing.

neufer wrote:

beyond wrote:
Neufer-neufer, He's our man; if he can't find information on it, no-one can. Inner-space outer-space really doesn't matter, He'll get you the information quicker than a Mad Hatter. It may not be quite what you were looking for, but then again - it's never a bore. He'll throw at you facts and figures and even a little folk-lore. His loquacious way is known far and wide and from it HE cannot hide. Though he may speak from many a name, the end result is always the same.
There-fore today, in his Honor, i present a new term -- Neufermation. You could say it is very Artsy.

Well, I couldn't write my own poem for Owlice, so I guess this is the next best thing.

beyond wrote:There-fore today, in his Honor, i present a new term -- Neufermation. You could say it is very Artsy.

beyond wrote:
Neufer-neufer, He's our man; if he can't find information on it, no-one can. Inner-space outer-space really doesn't matter, He'll get you the information quicker than a Mad Hatter. It may not be quite what you were looking for, but then again - it's never a bore. He'll throw at you facts and figures and even a little folk-lore. His loquacious way is known far and wide and from it HE cannot hide. Though he may speak from many a name, the end result is always the same.
There-fore today, in his Honor, i present a new term -- Neufermation. You could say it is very Artsy.

neufer wrote:

http://www.brainyquote.com/quotes/authors/y/yogi_berra.html wrote:

Yogi Berra quotes:

beyond wrote:
Baseball had it's Yogi Berra - and now i see Apod has a Yogi we have to beara.
Lets hope he doesn't 'strike-out' toooo much

http://www.brainyquote.com/quotes/authors/y/yogi_berra.html wrote:

Yogi Berra quotes:

A nickel ain't worth a dime anymore.

All pitchers are liars or crybabies.

Always go to other people's funerals, otherwise they won't come to yours.

Baseball is ninety percent mental and the other half is physical.

Congratulations. I knew the record would stand until it was broken.

Even Napoleon had his Watergate.

Half the lies they tell about me aren't true.

He hits from both sides of the plate. He's amphibious.

How can you think and hit at the same time?

I always thought that record would stand until it was broken.

I just want to thank everyone who made this day necessary.

I never blame myself when I'm not hitting. I just blame the bat and if it keeps up, I change bats.
After all, if I know it isn't my fault that I'm not hitting, how can I get mad at myself?

I never said most of the things I said.

I think Little League is wonderful. It keeps the kids out of the house.

I wish I had an answer to that because I'm tired of answering that question.

I'm a lucky guy and I'm happy to be with the Yankees. And I want to thank everyone for making this night necessary.

I'm not going to buy my kids an encyclopedia. Let them walk to school like I did.

If people don't want to come out to the ball park, nobody's gonna stop 'em.

If the world was perfect, it wouldn't be.

If you ask me anything I don't know, I'm not going to answer.

If you come to a fork in the road, take it.

If you don't know where you are going, you might wind up someplace else.

In baseball, you don't know nothing.

In theory there is no difference between theory and practice. In practice there is.

It ain't over till it's over.

It ain't the heat, it's the humility.

It gets late early out there.

It was impossible to get a conversation going, everybody was talking too much.

It's like deja-vu, all over again.

It's pretty far, but it doesn't seem like it.

Little League baseball is a very good thing because it keeps the parents off the streets.

Nobody goes there anymore. It's too crowded.

Slump? I ain't in no slump... I just ain't hitting.

So I'm ugly. So what? I never saw anyone hit with his face.

The future ain't what it used to be.

The other teams could make trouble for us if they win.

The towels were so thick there I could hardly close my suitcase.

There are some people who, if they don't already know, you can't tell 'em.

We have deep depth.

We made too many wrong mistakes.

When you arrive at a fork in the road, take it.

You better cut the pizza in four pieces because I'm not hungry enough to eat six.

You can observe a lot by just watching.

You should always go to other people's funerals, otherwise, they won't come to yours.

You wouldn't have won if we'd beaten you.

You've got to be very careful if you don't know where you are going, because you might not get there.

owlice wrote:Thanks, Yogi!

Chris Peterson wrote:

Don Lund wrote:Umm, OK. But if DM behaves like any other matter in terms of its gravitational effects, why doesn't it orbit the galactic center faster near the center than it does much further out? My idiot impression is that DM is sort of gluing the galaxy together so that it rotates in a semi-rigid way, and somehow that just doesn't seem to make sense...

It is orbiting faster near the center. The dark matter halo is a lot larger, and a lot more massive, than the ordinary matter. So the entire gravitational environment around a galaxy is altered by its presence. In particular, the DM halo is spherical, and for any visible component of the galaxy, most of the mass will be outside its orbital radius.

The dark matter isn't strictly gluing anything together, although the analogy isn't too bad. And a galaxy doesn't rotate as if it were rigid- the inner stars orbit faster than the outer ones. It's just that the difference in rotational velocity is smaller than can be explained if the visible mass is all there is.

nstahl wrote:
Thank you neufer. That's fascinating.

It explains how density waves could occur but brings up questions of how such correlated orbits came about.

Don Lund wrote:Umm, OK. But if DM behaves like any other matter in terms of its gravitational effects, why doesn't it orbit the galactic center faster near the center than it does much further out? My idiot impression is that DM is sort of gluing the galaxy together so that it rotates in a semi-rigid way, and somehow that just doesn't seem to make sense...

Alignment of spin axis with cosmic voids
Recent results suggest that the orientation of the spin axis of spiral galaxies is not a chance result, but instead they are preferentially aligned along the surface of cosmic voids. That is, spiral galaxies tend to be oriented at a high angle of inclination relative to the large-scale structure of the surroundings. They have been described as lining up like "beads on a string," with their axis of rotation following the filaments around the edges of the voids.

The explanation involves the presence of a large amount of dark matter, which is like any other matter in terms of its gravitational effects, but doesn't interact with electromagnetic radiation, so is essentially invisible to us.

Chappy wrote:They spin at almost exactly the same rate at the center as they do at the edge, meaning that something is basically holding it all together as one solid kinda piece.
The leading hypothesis of course, is that space & time constitute a fabric like substance due to dark matter/energy, and because of being suspended, so to speak, in this fabric, the entire Galaxy spins as a single object while individual objects within the galaxies are doing there own thing...kinda...in a way...sorta.

Chappy wrote:
From what I understand, and it is limited, Galaxies do rotate, but unlike how you would think. Since the laws of physics state that a spinning object rotates faster the closer you get to it's rotational center, you would expect Galaxies to basically spin themselves to pieces since they are not a solid piece of matter, and the outer arms would lag so far behind that it would be a jumbled mess in no time....but they don't.

They spin at almost exactly the same rate at the center as they do at the edge, meaning that something is basically holding it all together as one solid kinda piece.

http://en.wikipedia.org/wiki/Spiral_galaxy wrote:

Explanation of spiral galaxy arms made up of elliptical orbits.

---

The first acceptable theory for the spiral structure
was devised by C. C. Lin and Frank Shu in 1964.

* They suggested that the spiral arms were manifestations of spiral density waves.

* They assumed that the stars travel in slightly elliptical orbits and that the orientations of their orbits is correlated i.e. the ellipses vary in their orientation (one to another) in a smooth way with increasing distance from the galactic centre. This is illustrated in the diagram. It is clear that the elliptical orbits come close together in certain areas to give the effect of arms. Stars therefore do not remain forever in the position that we now see them in, but pass through the arms as they travel in their orbits.