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Sanborn Chase
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Why do the arms of spiral galaxies usually bifurcate? Is the visible matter in them moving in or out from the center?
Sanborn Chase said:Why do the arms of spiral galaxies usually bifurcate? Is the visible matter in them moving in or out from the center?
ohh yeah ?rexregisanimi said:One thing to keep in mind is that spiral arms in galaxies are "density waves" and not actual structures of the matter. They represent the area where many millions of stellar orbits reach their maximum distance from the galactic center of mass. At this point they are traveling the slowest and so "pile up" in the region producing the appearance of more stars than in-between the arms. But the individual stars in each arm are changing continuously.
Put another way, the arms are an illusion. They aren't like a whirlpool or anything like that.
davenn said:2 armed galaxies are only one of many forms, many have multiple arms, many have none that can be easily identified
Chronos said:The stars in a galaxy really are [were, given the finite speed of light] where they appear to be as Dave noted, however, Rex is correct in that they do not form and remain in spiral arms as they orbit a spiral galaxy. Their individual motions follow a density wave profile as illustrated here .
Yes, an electrical type transformer in its form. And Mr. Bernhardt cautioned me about posting pet theories, personal opinions, etc. I trust I haven't bent the pipe.rexregisanimi said:Excellent video!
Sanborn Chase, do you mean an electric transformer?
Sanborn Chase said:As the galaxy itself is moving through space(and time) would it not form the basic configuration of a transformer?
I'm curious what characteristic led you to that conclusion. I must be missing something because I just don't see it at all. I mean, I know that it's NOT, I'm just curious why you think it might be.Sanborn Chase said:Yes, an electrical type transformer in its form.
Probably because of near or actual collision with other galaxies,Sanborn Chase said:Why do the arms of spiral galaxies usually bifurcate? Is the visible matter in them moving in or out from the center?
A galaxy has a purpose?Sanborn Chase said:... Their forms must follow their purposes.
Say which what?Sanborn Chase said:spiral galaxies when considered over time seem to describe a form similar to an electrical transformer.
I think we're all confused why a galaxy seems related to an electrical transformer. Perhaps you could explain what you mean?Sanborn Chase said:Have I said something heretical? Is it not proper to assume the stars have arranged themselves so for a reason, and this may be worthy of our scrutiny?
No, the stars do not "arrange themselves". That puts an anthropomorphic spin on inanimate objects and thus is not science. Studying how the stars are arranged is certainly a valid (and interesting) field of study but let's not bring consciousness into it.Sanborn Chase said:Is it not proper to assume the stars have arranged themselves so for a reason, and this may be worthy of our scrutiny?
And you STILL have not explained this apparently nonsensical statement. Please do so.Sanborn Chase said:I may have been misunderstood by Mr. Phinds; spiral galaxies when considered over time seem to describe a form similar to an electrical transformer. I don't believe they are electrical transformers, although they may be. I'm trying to understand the reasons for the various forms galaxies take on as they transform one or more things into others. Their forms must follow their purposes.
Ah, where's the fun in that. It leaves me nothing to nitpick about.Sanborn Chase said:Mr. Phinds: please change "arrange themselves" to "are arranged".
Well, some of us here are just wading.Incidentally, my wife, who is also a heavenly body, agrees with you wholeheartedly that I'm nonsensical and not very scientific. I've informed her that someone who obviously resides in a very deep pool of knowledge agrees with her.
Spiral galaxies have arms that bifurcate due to a combination of two factors: gravity and differential rotation. The gravity of the galaxy's central bulge pulls on the stars and gas in the disk, causing them to form a spiral pattern. At the same time, the disk is rotating at different speeds, with the inner parts moving faster than the outer parts. This differential rotation causes the spiral arms to wind up and eventually bifurcate, creating multiple branches.
The movement of material in and out of spiral arms is primarily driven by gravitational forces. The central bulge of the galaxy exerts a strong gravitational pull on the stars and gas in the disk, causing them to move towards the center. However, the spiral arms themselves also contain pockets of gas and dust that can collapse and form new stars, causing material to move away from the arms. Additionally, interactions with neighboring galaxies or other external forces can also affect the movement of material in and out of the spiral arms.
No, not all spiral galaxies have arms that bifurcate. Some spiral galaxies have tightly wound arms that do not split into multiple branches. This can be due to a variety of factors, such as the mass and density of the galaxy's central bulge, the amount of gas and dust in the disk, and the speed of rotation. The exact formation and structure of spiral arms is still an area of active research in astrophysics.
There is no specific direction in which spiral arms bifurcate. The direction of bifurcation can vary among different spiral galaxies and can also change over time. This is due to the complex interplay of factors such as gravity, rotation, and external influences. Observations have shown that some spiral galaxies have arms that bifurcate in a spiral pattern, while others may have more of a branching pattern.
Yes, the movement of material in and out of spiral arms can affect the overall structure of a galaxy. The formation of new stars in the arms can change the mass distribution and alter the gravitational forces within the galaxy. This can result in the rearrangement of material and potentially even the formation of new spiral arms. Additionally, interactions with other galaxies or external forces can also greatly impact the structure of a spiral galaxy over time.