Solar System 'traverses all of the spiral arms of the Milky Way during 225my orbit ?!

???...!!!
So...ASTRO BO...err, paddoboy, are we all to believe that you are the only Member of SciForums that is actually learned in the real Academia, and the only Member on 'this "quasi peer review board" ' that will decide when such "supporting evidence" is presented...
...and you Post about other Members "suffering" from 'Tall Poppy Syndrome' and 'Delusions of Grandeur'...???...!!!


At any rate, continue to "Waffle" all you want, paddoboy, that is still not a substitute for providing supporting evidence of your 'claim' :

 

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Certainly not. I recognise many here with far greater capabilities in science then I. You just aint one of them.
And I'm not real sure what your reference to me as ASTRO BOY on another forum has to do with this but anyway, whatever entertains you... :shrug:

It appears that most others see you as doing the waffling, as usual. I'm just quoting standard mainstream theories, and that says that the Sun traverses all of the spiral arms of our galaxy.

 

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U = 10 km/s (radially inwards)
V = 5 km/s (in the direction of Galactic rotation)
W = 7 km/s (northwards out of the plane of the Galaxy)

Of course the Sun won't keep on going in this direction forever. In fact we approximate it's motion by an 'epicycle' on top of the mean motion around the Galaxy. The period of oscillation in and out of the plane of the galaxy (up and down) is about 70 million years. This means that we pass through the Galactic midplane about every 35 million years which some people have compared with the period between mass extinctions on Earth to come up with yet another doomsday theory. In fact it is true that the number of cosmic rays which hit the Earth will increase during the (about a) hundred thousand years we are closer to the Galactic plane. There have also been some plausible theories about the overall temperature of the Earth increasing (with the relevent climatic changes that implies).
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The above from origin's link in post 4.

Curiously, I'm just wondering if the three movements through these spiral arms, inwards, rotation about center of mass, and osscillating up and down, could have anything to do with another theory re extrasolar planets and "Hot Jupiters" with regards to planetary migration.
Just a thought.

 

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So..."just quote" the part of the "standard mainstream theories,...that says that the Sun traverses all of the spiral arms of our galaxy", in one orbit of our galaxy.

Or, just continue to "Waffle", paddoboy, that is still not a substitute for providing supporting evidence of your 'claim' :

 

You must take the time to study the scientific methodology.
The onus of proof is on you.

Once again, current accepted scientific theory says the Sun orbits our galactic center, and passes through all "density wave" induced spiral arms.

 

In defence of dmoe's position though, just as on face value, the Sun could be said to orbit the Earth, when we apply a bit of critical thinking, it can be seen that it is the Earth orbiting the Sun.
Of course in actual fact the Sun and Earth orbit each other, but the center of gravity is deep withing the Sun's surface.
Likewise on amateurish face value, it could be said that the Sun/planet system, moves as one with the galactic arm.
But again a bit of critical thinking reveals that if that was to happen, an effect called the winding problem would be evidenced, as the galactic arms become more "tightly wound".

The success of "density wave" theory has seen it now applied to Saturn's rings.

...A rundown on the "density wave" theory at.
http://en.wikipedia.org/wiki/Density_wave_theory
[noting of course that WIKI is many rungs further up the ladder than is the religiously inspired "conservapedia" ]
just saying.

OK Russ?

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Games???!!!

So...you just continue to"Play Games" and "Waffle", paddoboy?
Neither is a substitute for providing supporting evidence of your 'claim' :

 

Let's check what origin's referenced site, "Ask an Astronomer" has to say about that :

- the ^^above quoted^^ from : http://curious.astro.cornell.edu/question.php?number=461

Mind you, this is from a site that origin evidently considers to be 'reputable'.

 

Along with the curiosity questions above, climate change, Asteroid/Comet bombardments, especially perturbations from the Oort cloud and also mass extinctions, would be tied in with our movements through the galactic spiral arms and density waves.

Maybe I've stumbled on something.....YEC's and other God botherer types would obviously be somewhat oppressed by the accepted density wave theory, the same as they are oppressed by most scientific theories in general.
The winding problem would be one that they enjoy, along with the fact spirals are thought to be older.......

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"Most spiral arms in galaxies are density waves, which are compression waves (like sound) that travel through the disk and cause a piling-up of stars and gas at the crest. The wave is temporarily sustained by the force of its own gravity, but it eventually wraps up or gets absorbed at orbital resonances, places where random stellar oscillations have the same period as the local wave.
http://www.scientificamerican.com/article/what-process-creates-and/
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Take note dmoe:
The earth/Moon system's centre of gravity is within the Earth.....
The Earth/Sun system's center of gravity is within the bounds of the Sun...
The Jupiter/Sun system's center of gravity is just barely outside the Sun....
The Solar system's center of gravity is somewhere near the Sun, but varies upon the orbital positions of the planets.

 

http://en.wikipedia.org/wiki/Barycentric_coordinates_(astronomy)

 

No, no dmoe, You misunderstand. It's not my claim. I'm simply standing on the shoulders of giants. I'm stating an accepted theory.
It's actually the accepted theory to explain spiral arms via density waves, first put forward by Bertil Lindblad in about 1925, then researched on much further by Lin and Shu in the mid-1960s.
Something a very reputable Astronomer informed me of over a couple of decades ago, when I was of the same mistaken belief as yourself.

Here's some more literature to help you.
http://casa.colorado.edu/~danforth/science/spiral/#SECTION0002000
Lin and Shu theorized that spiral density waves are simply the most dominant mode of galactic instabilities and are more or less constant over time. If the value of Q is small, these waves are the closest of any modes to instability and thus will grow to the largest amplitude. Clearly there will be damping at the Lindblad radii, but over time the swing amplification and the damping should reach equilibrium and these spiral modes will be maintained indefinitely (BT94).
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http://www.space.com/24642-spiral-galaxies-milky-way-shape-explained.html

http://www.castlerock.wednet.edu/HS/stello/Astronomy/TEXT/CHAISSON/BG314/HTML/BG31404.HTM


If that doesn't convince you, then the onus is on you to invalidate current theory, or come up with a new hypothesis for us to see.
I doubt you are able to do that so, I'll leave it there at this time and hope you are able to accept the decision of your peers on this forum, and the mainstream scientific community in general.


If you are still having problems accepting mainstream theory, why not start a thread in Alternative hypothesis section, and see where it leads you?
It may even reveal to you why the BB is so well accepted.
Just read those 12 points I did start a thread on for the Alternative people, be prepared to "run the gauntlet" listen, and most Importantly, admit that you probably are wrong.
Remembering dmoe, that all current theories had to also run that same gauntlet.
Some are now near certain, as I have mentioned more than once.

 

Here is an Interesting article about density waves and their application to the rings of Saturn that I mentioned in an earlier post.........
A relevant extract to what I was alluding to is as follows......
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http://www.universetoday.com/10545/cassini-determines-the-density-of-saturns-rings/

The dramatically varying structure of ring B is in sharp contrast to the relatively flat structure of ring A or the gentle, wavy structure of ring C, where many dense, narrow and sharp-edged ringlets permeate its outer part.

Cassini also detected more than 40 wavy features called “density waves” in ring A, many near its outer region, close to the moons orbiting just outside the ring. The density wave observations will tell more about the ring surface mass density, its vertical thickness and other physical properties.

“A marvelous array of waves, caused by gravitational interactions with nearby moons, has been uncovered throughout ring A,” said Marouf. “We also see a major density wave in the dense ring B. Some of these waves have been seen in Voyager and other Cassini observations, but not in this large number and not with this exceptional clarity.”
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Other "rare" occurrences, due to gravitational interactions and perturbations concern the two small moons of Saturn called Prometheus and Pandora, that have actually been shown to stabilize the structure of one of Saturn's rings, and are appropriately called "Shepherd moons".

Staying with Saturn, another unusual "gravity feat" concerns two moons, "Janus and Epimithetheus" that virtually perform an orbital swap.

Just thought that maybe interesting.

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Just to illustrate that point more than I did previously......When Saturn and Jupiter are on one side of the Sun, the center of mass of the system will change.
That was also inferred in one of Trippy's links.

 

Yes, the reputable site (Cornell U.) discussed orbits. So what's your point?

 

@ paddoboy

Since I OP'd this thread, paddoboy, you have made 17 Posts. In none of those 17 Posts have you supplied any "supporting evidence" to back up your 'claim' :

You have, however, made "assumptions" and "allegations", proffered "advice", made "ad hominem attacks" and attempted to "erect Straw Men" arguments.
Post #7 :

Post #9 :

Post #14 :

There is no reason for me to point out the "Waffling" in your other 14 Posts in this Thread.

paddoboy, no where in the OP, nor in any other of my Posts in this Thread have I made any 'claim' stating "that we only travel in one spiral arm" while our Solar System orbits the center of the Milky Way galaxy!

See my statement from my OP :

And my statement from my Post #8 :

paddoboy, in his Post #4, origin "quoted" Karen Masters from the "Ask An Astronomer" section of "Curious About Astronomy?" site from Cornell University. :

- the ^^above quoted^^ from : http://curious.astro.cornell.edu/question.php?number=402

origin considered Cornell University a 'reputable' source to 'cite'.
I, myself, dmoe, consider Cornell University a 'reputable' source to 'cite'.
I would expect that most other Members of SciForums would consider Cornell University a 'reputable' source to 'cite'.

paddoboy, have you considered applying some "simple math" to the information presented in that 'cited reputable source'?

Let us apply some "simple math" :
To Wit : "We pass through a major spiral arm about every 100 million years, taking about 10 million years to go through."
From the above, it should be 'inferred', or indeed understood(through "simple math"), that in ~225 million years our Solar system would only "pass through", or "traverse" 2 "major spiral arm(s)"...
...have I, in your words, "probably misinterpreted what (I, dmoe) thought (I, dmoe) learnt" of "simple math", paddoboy?

At the "atlasoftheuniverse.com" site, is presented "A Map of the Milky Way".

- the ^^above quoted^^ from, and much more at : http://www.atlasoftheuniverse.com/milkyway.html

paddoboy, no other Member of SciForums should be 'expected to', nor 'relied upon' to do "your own homework" for you!

From your own 17 Posts, paddoboy, and any other Members Posts of 'cited reputable sources', there is still no "evidence supporting" your 'claim' :

Will you 'claim' this Post to be 'confusing' ?

Will you 'claim' this Post to be 'pedantic' ?

Will you 'claim' this Post to be 'the usual' ?

Will you continue to "Waffle" ?

 

Recent observations have shown that there are 4 spiral arms, not two as was previously thought. http://www.sci-news.com/astronomy/science-milky-way-galaxy-four-spiral-arms-01649.html For the solar system to pass through all four arms in 1 galactic year means we're moving four times as fast as the arms themselves. We don't move that fast. We do 'wobble' above and below the ecliptic,(I think at about +- 23 degrees), but we remain pretty much in the same place with respect to the spiral arm we're in.

 

You may want to "catch up" with what you consider 'certain', paddoboy.

Peruse the following, possibly :

- the ^^above quoted^^ from, and more at : http://www.universetoday.com/85300/a-new-spin-on-galactic-evolution/
- the ^^above quoted^^ article references the Royal Astronomical Society’s National Astronomy Meeting in Wales on April 20, 2011 - more at this Link :http://www.ras.org.uk/news-and-pres...ew-theory-of-evolution-for-spiral-galaxy-arms

And also, possibly :

- the ^^above quoted^^ from, and more at : http://www.universetoday.com/86056/testing-the-spiral-density-wave-theory/
- the ^^above quoted^^ article references "OBSERVATIONAL EVIDENCE AGAINST LONG-LIVED SPIRAL ARMS IN GALAXIES", which is viewable as a "free" .pdf at this Link : http://arxiv.org/PS_cache/arxiv/pdf/1105/1105.5141v1.pdf

In Real Science, paddoboy, any "perceived" or "assumed" concepts such as 'certainty', 'fact' or even 'well accepted' relative to most "hypotheses" and "theories", is NOT a fundamental tenet that is taught to, learned or practiced by Real Scientists.
This is simply because the majority of any "perceived" or "assumed" 'certainty's' and 'facts' have turned out, over time, to be merely "fleeting" or "transient".
That, paddoboy, is why Real Science continues to accrue and advance our knowledge of the Natural Universe, instead of stagnating by only relying on knowledge gleaned from past achievements or discoveries.

 

Thank you, AlexG, for helping to "clarify the issue", as I requested in my OP.

What you stated in your Post coincides with what I myself was taught and have continued to learn, through Real Academia(as opposed to the "Internet" or 'Internet Forums' I must add!), of the 'orbit' of our Solar System within the Milky Way Galaxy.

I "Thank You" again, AlexG, for your contribution to this Thread.