Arp 147: two gravitationally interacting galaxies. The two galaxies happen to be oriented so as to resemble a number 10. The left-most galaxy, or the "one" in this image, is relatively undisturbed apart from a smooth ring of starlight. It appears nearly on edge to our line of sight. The right-most galaxy, resembling a zero, exhibits a clumpy, blue ring of intense star formation. The blue ring was most likely formed after the galaxy on the left passed through the galaxy on the right propagating a circular density wave at the point of impact. As this density wave collided with material in the target galaxy that was moving inward due to the gravitational pull of the two galaxies, shocks and dense gas were produced, stimulating star formation. The dusty reddish knot at the lower left of the blue ring probably marks the location of the original nucleus of the galaxy that was hit...Boom!
Using both ESA/ESO/NASA provided software and Photoshop I processed three b&w Hubble Telescope images (courtesy NASA and MAST) captured with wide-band filters at 450nm (blue), 606nm (orange), 814nm (near IR).