Science
Related: About this forumThe Making of a Monster, Caught by Accident
By Phil Plait
One of the most overwhelming things we have learned from studying astronomy in the past centuryand its quite a listis that entire galaxies collide.
I cannot overstate how awe-inspiring that is. A galaxy is a vast thing: a self-gravitating collection of tens or hundreds of billions of stars, countless clouds of gas and dust massive enough to create billions more stars, and all of this (not including the dark matter, which we cannot directly see) spread out over a hundred thousand light yearsa million trillion kilometers.
By itself a galaxy is mind-crushing structure. But then to find that they can careen through space and physically collide with another such monster
its difficult to grasp the enormity of such an event.
And yet collisions happen, and they happen often. And when they do, the result can be such beauty as to make even the most jaded cynic weep:
much more
http://www.slate.com/blogs/bad_astronomy/2013/07/01/when_galaxies_collide_hubble_spies_a_massive_cosmic_train_wreck.html
BlueToTheBone
(3,747 posts)all we have to do is look at this picture. These are galaxies. It's almost incomprehensible.
Thank you for your great contribution to my awesomeness picture library!
localroger
(3,626 posts)The Andromeda galaxy is headed for a collision with our own Milky Way, the end result of which is expected to be a single elliptical form galaxy. There's a good chance the Earth will still be around when this happens.
Fortunately, it's very unlikely that the Sun will hit or get too close to one of the Andromedan (?) stars whizzing through; galaxies have a lot of stars but they have even more vast empty space.
liberalla
(9,247 posts)Thanks.