New Hubble Images of Galaxy collisions

Many astronomical textbooks say that galaxies are stable objects, however, they do have a side of them that is dynamic.

There are times when galaxies collide and merge together, forming beautiful and astonishing views of new star births, spectacular shapes and much more. In honor of the Hubble's 18th launch anniversary, 59 images of colliding galaxies have been released to the public.
Long ago, when the expanding Universe was much smaller than it is today, mergers and collisions were far more common. However, now it is now harder to observe, because there are far less collisions.

Galaxies collide at an extremely slow rate, according to human standards. But when they do collide, it is a great sight to see.
Some of the new images can be found here: http://www.nasa.gov/mission_pages/hubble/science/hst_img_20080424.html