by ems57fcva » Sat Oct 20, 2012 1:31 am
I have my own views if how galaxies merge, and so I have a different interpretation on this altogether. I do agree this this is a galaxy merger, and that the two original galaxies are stretched out in this image, with their cores merging in the center. However, when I see pictures of galaxies merging, I see early on a bridge develop between the galaxies that the simulations do not recreate. When this bridge becomes dominant, it seems to become the bar in a barred spiral galaxy with the remains of the original galaxies being the arms of the barred spiral. If the merging galaxies were spirals, then their arms become secondary arms in the merged galaxy. I also believe that as the merged galaxy ages. it wraps itself tighter and tighter until (if left undisturbed) it becomes a grand spiral with a tight core and well wrapped spiral arms.
So what do I think that we are seeing here? I think that this is a merger at the stage where it is a loose barred spiral, and that we are looking straight down the bar. The merger appears to be between a larger galaxy and a smaller one. The remains of the larger galaxy mostly are to the left of the central core/bar in this image, but if you look at the lower right of the center, you see a blue blob that is similar in color to the "arm" on the left. That is the start of that arm. It wraps around behind the core and then appears again at the upper left of the core and heads on out.
The remains of the smaller galaxy start behind the core/bar from our point of view. That arm comes out on the left side of the core/bar, goes in front of it, and then curves around and heads back behind the core/bar again. A branch does head off to the right, and I assume that this is a tidal tail.
In addition, orange tendrils of gas and dust can be seen being pulled off of the nearer sections of the original-galaxies/arms and into the still forming core of the new galaxy.
So that is my alternate view of things. My overall opinion is that galaxy mergers are not well understood at all, and that there is much to learn about galaxies and the dark matter. Especially troubling to me is that the simulations that I see of mergers all fail to reproduce the bridge that I see between the interacting galaxies such as the Antenna galaxies. I repeat that the only reason that a bridge is not visible here is that we are looking straight down it. So this is an alternate and possibly very enlightening image of a loose barred spiral galaxy IMO.
Edward Schaefer
I have my own views if how galaxies merge, and so I have a different interpretation on this altogether. I do agree this this is a galaxy merger, and that the two original galaxies are stretched out in this image, with their cores merging in the center. However, when I see pictures of galaxies merging, I see early on a bridge develop between the galaxies that the simulations do not recreate. When this bridge becomes dominant, it seems to become the bar in a barred spiral galaxy with the remains of the original galaxies being the arms of the barred spiral. If the merging galaxies were spirals, then their arms become secondary arms in the merged galaxy. I also believe that as the merged galaxy ages. it wraps itself tighter and tighter until (if left undisturbed) it becomes a grand spiral with a tight core and well wrapped spiral arms.
So what do I think that we are seeing here? I think that this is a merger at the stage where it is a loose barred spiral, and that we are looking straight down the bar. The merger appears to be between a larger galaxy and a smaller one. The remains of the larger galaxy mostly are to the left of the central core/bar in this image, but if you look at the lower right of the center, you see a blue blob that is similar in color to the "arm" on the left. That is the start of that arm. It wraps around behind the core and then appears again at the upper left of the core and heads on out.
The remains of the smaller galaxy start behind the core/bar from our point of view. That arm comes out on the left side of the core/bar, goes in front of it, and then curves around and heads back behind the core/bar again. A branch does head off to the right, and I assume that this is a tidal tail.
In addition, orange tendrils of gas and dust can be seen being pulled off of the nearer sections of the original-galaxies/arms and into the still forming core of the new galaxy.
So that is my alternate view of things. My overall opinion is that galaxy mergers are not well understood at all, and that there is much to learn about galaxies and the dark matter. Especially troubling to me is that the simulations that I see of mergers all fail to reproduce the bridge that I see between the interacting galaxies such as the Antenna galaxies. I repeat that the only reason that a bridge is not visible here is that we are looking straight down it. So this is an alternate and possibly very enlightening image of a loose barred spiral galaxy IMO.
Edward Schaefer