02-07-2018, 03:27 PM
The beauty of galactic cannibalism
Some recent stunning images from the CFHT on MK have shown that was once thought to be a relatively quiescent group of galaxies shows that there's a little more going on, specifically described as "galactic cannibalism".
https://goo.gl/NkeRjH
"Due to its unique features, Stephan's Quintet has been widely observed across the entire electromagnetic spectrum, and has been the subject of many complex numerical simulations. The team detected a red halo composed of old stars centered on a galaxy, NGC 7317. NGC 7317 was thought to be in a stable state or recently arrived near the group. The detection of red stars implies the contrary, that this galaxy has been interacting for a very long time with the other members of the group. Interactions such as the one seen in these observations are called galactic cannibalism. Galactic cannibalism occurs when the gravitational forces from a larger galaxy or group of galaxies slowly tear apart a smaller galaxy. Characteristic features of galactic cannibalism are streams or halos of stars orbiting the larger galaxy, like the halo of red stars seen around NGC 7317. A first implication is that Stephan's Quintet is far older than currently admitted. The models of formation and evolution of this emblematic system will have to be revised. This global case of galactic cannibalism should eventually lead to the formation of a giant elliptical galaxy."
Some recent stunning images from the CFHT on MK have shown that was once thought to be a relatively quiescent group of galaxies shows that there's a little more going on, specifically described as "galactic cannibalism".
https://goo.gl/NkeRjH
"Due to its unique features, Stephan's Quintet has been widely observed across the entire electromagnetic spectrum, and has been the subject of many complex numerical simulations. The team detected a red halo composed of old stars centered on a galaxy, NGC 7317. NGC 7317 was thought to be in a stable state or recently arrived near the group. The detection of red stars implies the contrary, that this galaxy has been interacting for a very long time with the other members of the group. Interactions such as the one seen in these observations are called galactic cannibalism. Galactic cannibalism occurs when the gravitational forces from a larger galaxy or group of galaxies slowly tear apart a smaller galaxy. Characteristic features of galactic cannibalism are streams or halos of stars orbiting the larger galaxy, like the halo of red stars seen around NGC 7317. A first implication is that Stephan's Quintet is far older than currently admitted. The models of formation and evolution of this emblematic system will have to be revised. This global case of galactic cannibalism should eventually lead to the formation of a giant elliptical galaxy."