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This is a link for a very interesting and intriguing article on star formation from SCIENTIFIC AMERICAN Magazine. Makes you rethink what we assume we already understood about star and galactic formation and their evolution. http://www.scientificamerican.com/ar...T_SPC_20100211
It's always good to have more confirmation. I'm not surprised by it though. It seems like it would be reasonable that in the early formation of the universe, and after gasses had formed, things would've been fairly dense, but clumpy. These clumps may have been the first formation of a protogalaxy. Because these early galaxies would be gas, the gasses would likely function as a stellar nursery, and generating the first formation of stars. This is the same thing we see in stellar nurseries today. That would seem to suggest that galaxies (in the form of gas clumps) may have been first to form, followed by the formation of stars within the galaxies.
One of the reasons why star formation isn't as active in the Milky Way galaxy, is because a lot of the gasses have been used up. Perhaps when the M-31 galaxy (Andromeda galaxy) collides with the Milky Way, and form a supergalaxy, there might be enough gas combined to continue forming stellar nurseries and stars for a while.
Hmm, I've kind of wondered if the Andromeda galaxy is heading for ours, or is ours heading toward the Andromeda galaxy, or are they both moving toward each other?
It's always good to have more confirmation. I'm not surprised by it though. It seems like it would be reasonable that in the early formation of the universe, and after gasses had formed, things would've been fairly dense, but clumpy. These clumps may have been the first formation of a protogalaxy. Because these early galaxies would be gas, the gasses would likely function as a stellar nursery, and generating the first formation of stars. This is the same thing we see in stellar nurseries today. That would seem to suggest that galaxies (in the form of gas clumps) may have been first to form, followed by the formation of stars within the galaxies.
One of the reasons why star formation isn't as active in the Milky Way galaxy, is because a lot of the gasses have been used up. Perhaps when the M-31 galaxy (Andromeda galaxy) collides with the Milky Way, and form a supergalaxy, there might be enough gas combined to continue forming stellar nurseries and stars for a while.
Hmm, I've kind of wondered if the Andromeda galaxy is heading for ours, or is ours heading toward the Andromeda galaxy, or are they both moving toward each other?
That's a good question...I think both galaxies are moving towards one another???
I think you are correct...we always assume that most matter will be visible and/or luminous..IMHO...this is an invalid assumption. Looking at the COBE satellite results shows the initial "clumpiness" of our Universe; there was probably much more gas at the beginning of the Big Bang and more matter and dust grains etc. than previously thought, this also would take some of the mystery out of "Dark Matter". It also could be WIMPS etc. IMHO....the Scientific American article is on the right track . http://en.wikipedia.org/wiki/Androme..._Way_collision
Nice simulation! While the merger would involve both galaxies, and there's no question that both galaxies are in motion, it's hard to guess if they are both moving toward each other. Although the Andromeda galaxy is very large, the Milky Way seems to be the largest galaxy in our local cluster of galaxies. It might be that the Andromeda galaxy is being pulled in (gravitational attraction) because of the greater mass of the Milky Way galaxy. The Milky Way would probably also be affected by such a gravitational tug-of-war, but maybe not as much.
It would also depend on how the galaxies within our local cluster are moving and moving in what direction. Somehow, I'm inclined to think they're all orbiting. And if the Milky Way is the galaxy with the strongest gravitational attraction, the others in our local cluster might be slowly orbiting around it as well as toward it. The Large and Small Magellanic Clouds (irregular dwarf galaxies) are already at the edge of the Milky Way and being pulled in.
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I think you are correct...we always assume that most matter will be visible and/or luminous..IMHO...this is an invalid assumption. Looking at the COBE satellite results shows the initial "clumpiness" of our Universe; there was probably much more gas at the beginning of the Big Bang and more matter and dust grains etc. than previously thought, this also would take some of the mystery out of "Dark Matter". It also could be WIMPS etc. IMHO....the Scientific American article is on the right track .
I don't know. I'm not so sure there was necessarily more matter (gas, dust, grains) in the early universe, but certainly it would have been more densely compressed than it is now. As the universe continued expanding and cooling, the density of the universe would become weaker as space itself became more expansive. There's a lot more space within the structure of the universe now, as shown in the simulations of the following post. But certainly matter that was more densely compressed in the early universe has gravitationally coalesced into the weird filaments we can detect today with would also seem to contribute to larger expansions of space within the universe. The bottom line would be that the overall mass of the universe is probably somewhat similar to the early universe, except that the dense compaction of it is growing thinner all the time as it continues expanding. To me, the images in the link below, also seem to suggest that the Big Crunch is probably unlikely. //www.city-data.com/forum/11219593-post22.html
Dark matter probably wouldn't be a major factor in the change of density of the early universe vs now. Dark energy might have a role though.
Nice simulation! While the merger would involve both galaxies, and there's no question that both galaxies are in motion, it's hard to guess if they are both moving toward each other. Although the Andromeda galaxy is very large, the Milky Way seems to be the largest galaxy in our local cluster of galaxies. It might be that the Andromeda galaxy is being pulled in (gravitational attraction) because of the greater mass of the Milky Way galaxy. The Milky Way would probably also be affected by such a gravitational tug-of-war, but maybe not as much.
It would also depend on how the galaxies within our local cluster are moving and moving in what direction. Somehow, I'm inclined to think they're all orbiting. And if the Milky Way is the galaxy with the strongest gravitational attraction, the others in our local cluster might be slowly orbiting around it as well as toward it. The Large and Small Magellanic Clouds (irregular dwarf galaxies) are already at the edge of the Milky Way and being pulled in.
I don't know. I'm not so sure there was necessarily more matter (gas, dust, grains) in the early universe, but certainly it would have been more densely compressed than it is now. As the universe continued expanding and cooling, the density of the universe would become weaker as space itself became more expansive. There's a lot more space within the structure of the universe now, as shown in the simulations of the following post. But certainly matter that was more densely compressed in the early universe has gravitationally coalesced into the weird filaments we can detect today with would also seem to contribute to larger expansions of space within the universe. The bottom line would be that the overall mass of the universe is probably somewhat similar to the early universe, except that the dense compaction of it is growing thinner all the time as it continues expanding. To me, the images in the link below, also seem to suggest that the Big Crunch is probably unlikely. //www.city-data.com/forum/11219593-post22.html
Dark matter probably wouldn't be a major factor in the change of density of the early universe vs now. Dark energy might have a role though.
Thanx, I thought it was a fantastic simulation too! I see your point about the Andromeda Galaxy...although it is more massive; apparently our galaxy may contain more Dark Matter(this is NEW information to me) Andromeda Galaxy - Wikipedia, the free encyclopedia
I also agree that the relative motions and directions of our local group are far too complex to give exact scenarios as to which galaxy is moving towards the other, but most scientists agree that they will "collide". Though a merger is a more accurate term and the galaxies are too diffuse to "actually" collide. It will be more like a great gravitional "dance".
Dark Energy would explain our Universe's accelerating expansion; but not it's initial density. I still think WIMPs and Neutrinos(some flavors) etc. may explain most of the missing mass(Dark Matter) Dark matter - Wikipedia, the free encyclopedia Neutrino - Wikipedia, the free encyclopedia Neutrino - Simple English Wikipedia, the free encyclopedia
Since Neutrinos are so persuasive and numerous in our Universe; just one or two flavors having any mass may explain the missing matter dilema.
I am not so sure that I am still a believer in the Big Crunch theory as I once was an advocate of the theory; but I still would not rule it out either. I now am inclined to believe in the Multiverse or Brane theory....which means that the Universe(s) will always be around...I hated the thought of entropy winning out and everything just fading away. That was part of the reason I liked the Big Crunch Theory, since the Universe continued that way. With the Multiverse/Brane theory...Universes go on indefinitely. http://en.wikipedia.org/wiki/Membrane_(M-Theory) Multiverse - Wikipedia, the free encyclopedia
Thanks for the sharp observation Pitts! You're absolutely right. I stand corrected about the sizes. Regardless, both are extremely large in our local cluster with a collision to occur in the distant future. It's possible, maybe even probable, that some stars, or even stellar clusters, from both galaxies may be flung out to drift alone in intergalactic space because of the merger.
I'm wondering if the video was cut a bit short. It seems like the end of it was pretty abrupt. I would've thought it would finish with more of the completion of settling down as a super galaxy.
Interestingly, there's some evidence that suggests that M-31 may have had a head-on collision with a neighboring dwarf galaxy, M-32. The disc of M-31 appears to be warped. It's kind of hard to tell what happened. You can see the outer ring with stars. Just inside the outer ring, looks like dust and fairly empty space. And further in is loosely organized spiral of stars. Could we be seeing an ancient shock wave from the collision? (Image 1)
M-31, is still a gigantic galaxy, though weakened from what its original self must have once been. Two dust rings (or holes), an inner and an outer, may be evidence of a collision. Could there have been more than one collision? (Image 2)
And another indicator of a collision is that the center of M-31 appears to have two galactic nuclei. (Image 3)
It's thought that our own Milky Way galaxy might be as large as it is from absorbing other galaxies (probably dwarf galaxies similar to the Magellanic Clouds). As galaxies go, on the galactic scale, collisions would be extremely powerful (albeit extremely slow) events. I agree that collisions of stars would be minimal if at all because of the vast distances between stars. Certainly stars would be pretty scattered following the collision, with most slowly being gravitationally pulled back into a spiral path of the new, improved galaxy.
You're probably right our galaxy is considered to have more mass. In fact, it looks like it has about 50% more mass than previously thought. The greater mass is related to a swifter spin. The solar system is traveling around the Milky Way at a speed of about 600,000 miles per hour. That's mind blowing! While M-31 is larger in size, it spins more slowly than the MilkyWay. It's thought the denser mass of our galaxy will have enough gravitational attraction to pull in M-31 (like being caught by a whirlwind), which is weaker. http://www.nrao.edu/pr/2009/mwrotate/
Thanks for the sharp observation Pitts! You're absolutely right. I stand corrected about the sizes. Regardless, both are extremely large in our local cluster with a collision to occur in the distant future. It's possible, maybe even probable, that some stars, or even stellar clusters, from both galaxies may be flung out to drift alone in intergalactic space because of the merger.
I'm wondering if the video was cut a bit short. It seems like the end of it was pretty abrupt. I would've thought it would finish with more of the completion of settling down as a super galaxy.
Interestingly, there's some evidence that suggests that M-31 may have had a head-on collision with a neighboring dwarf galaxy, M-32. The disc of M-31 appears to be warped. It's kind of hard to tell what happened. You can see the outer ring with stars. Just inside the outer ring, looks like dust and fairly empty space. And further in is loosely organized spiral of stars. Could we be seeing an ancient shock wave from the collision? (Image 1)
M-31, is still a gigantic galaxy, though weakened from what its original self must have once been. Two dust rings (or holes), an inner and an outer, may be evidence of a collision. Could there have been more than one collision? (Image 2)
It's thought that our own Milky Way galaxy might be as large as it is from absorbing other galaxies (probably dwarf galaxies similar to the Magellanic Clouds). As galaxies go, on the galactic scale, collisions would be extremely powerful (albeit extremely slow) events. I agree that collisions of stars would be minimal if at all because of the vast distances between stars. Certainly stars would be pretty scattered following the collision, with most slowly being gravitationally pulled back into a spiral path of the new, improved galaxy.
You're probably right our galaxy is considered to have more mass. In fact, it looks like it has about 50% more mass than previously thought. The greater mass is related to a swifter spin. The solar system is traveling around the Milky Way at a speed of about 600,000 miles per hour. That's mind blowing! While M-31 is larger in size, it spins more slowly than the MilkyWay. It's thought the denser mass of our galaxy will have enough gravitational attraction to pull in M-31 (like being caught by a whirlwind), which is weaker. http://www.nrao.edu/pr/2009/mwrotate/
Thanx N.B.. and I thank you, for pointing out the greater Mass of the Milky Way..I forgot it has been mathematically proven! As evidenced by the faster rate of rotation of the outer spiral bands of the Milky Way. Also proves that we have a Super Massive Black Hole at our Galactic Core and that the Milky Way, now appears as massive or more massive than Andromeda.
I did NOT watch the entire simulation from YouTube..I should have though. I have seen the entire simulation on the Science Channel...I'll try and find it. If I remember correctly both Galaxies merge as do their respective Galactic Central Black Holes; resulting in a Super Elliptical Galaxy?? Both galaxies lose their spiral arms from their gravitational interactions(I may NOT be remembering correctly???)
You're correct as far as I know and the resulting gravitional shock waves will result in a new burst of Star formation in the new Super Galaxy.
Also If I am WRONG about the collision forming an Ellipitical Galaxy...then it WAS a BARRED SPIRAL Galaxy for sure....( NEW DATA suggests that the Milky Way itself may be a Barred Spiral) I couldn't read ALL the data YET...BUT I will....LOL. I need another aspirin! .
Thanx N.B.. and I thank you, for pointing out the greater Mass of the Milky Way..I forgot it has been mathematically proven! As evidenced by the faster rate of rotation of the outer spiral bands of the Milky Way. Also proves that we have a Super Massive Black Hole at our Galactic Core and that the Milky Way, now appears as massive or more massive than Andromeda.
I did NOT watch the entire simulation from YouTube..I should have though. I have seen the entire simulation on the Science Channel...I'll try and find it. If I remember correctly both Galaxies merge as do their respective Galactic Central Black Holes; resulting in a Super Elliptical Galaxy?? Both galaxies lose their spiral arms from their gravitational interactions(I may NOT be remembering correctly???)
You're correct as far as I know and the resulting gravitional shock waves will result in a new burst of Star formation in the new Super Galaxy.
Also If I am WRONG about the collision forming an Ellipitical Galaxy...then it WAS a BARRED SPIRAL Galaxy for sure....( NEW DATA suggests that the Milky Way itself may be a Barred Spiral) I couldn't read ALL the data YET...BUT I will....LOL. I need another aspirin! .
Nice links and vids!
My understanding is like yours, that the Milky Way is now thought to be a barred spiral. The super galaxy could turn out to be an elliptical galaxy, but it might take a few billion years to know for sure. LOL! The final shape of the super galaxy would probably depend on a number of factors, any of which could change the outcome.
In addition to a flurry of star formation in the super galaxy, I would guess there might also be a flurry of stellar novas and supernovas. Good for the formation of new stars and planets, but maybe not so great for a number of inhabitated planets that are in the vicinity at the time.
My understanding is like yours, that the Milky Way is now thought to be a barred spiral. The super galaxy could turn out to be an elliptical galaxy, but it might take a few billion years to know for sure. LOL! The final shape of the super galaxy would probably depend on a number of factors, any of which could change the outcome.
In addition to a flurry of star formation in the super galaxy, I would guess there might also be a flurry of stellar novas and supernovas. Good for the formation of new stars and planets, but maybe not so great for a number of inhabitated planets that are in the vicinity at the time.
Thanks...I thought the additional videos and links provided a clearer understanding of Galactic mergers. It's true that a Galactic collision is really relatively slow compared to how we humans think. Even though both Galaxies are traveling at hundreds of thousands of miles per hour; the Galactic gravitional merger will actually take millions, if not billions of years.
You're right that the merger may well spell bad news for our solar system, sun and planet.. I have read that there is a good possibility that our spiral arm could be completely thrown out of both galaxies and/or completely destroyed. However the merger will bring new intensity to star formation and therefore rejuvenate both galaxies; as their respective new star formation is beginning to wane. It probably will also destroy life on most inhabited planets as their orbits will be completely changed.
I have some additional links on Dark Matter and it's possible constituents....along with WIMPS and additional Neutrino Flavors; Axions and Neutralinos may also contribute to the missing mass.
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