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This colliding pair is about 300 million miles away. Computer simulations say we are seeing two nearly identical spiral galaxies about 160 million years after they started colliding. Collision of galaxies is not like a car collision. Very little material actually hits other material. It is more of a distorting gravitational interaction. The long arm to the upper left is actually curved, but looks straight because we see it edge-on. They will merge and form a spherical elliptical galaxy. The blue regions are places where young hot new stars are forming.
Click the image to see a much larger version showing a multitude of tiny more distant galaxies all over the field of view.
The NASA Hubble Space Telescope view of this disk galaxy is nearly edge-on to our line-of-sight. A dark dust lane divides the galaxy into two halves. The image shows a subtle central bulge around a bright nucleus. Imagine two dinner plates with one upside-down on top of the other.
This dwarf and disorganized galaxy is 12.5 million light-years away. There are hundreds of thousands of blue and red stars in this Hubble Space Telescope image. Hot blue clusters of massive stars are scattered around the galaxy. New star birth regions show as reddish regions. Clouds of gas and dust are silhouetted against the starlight.
NGC 4449 has a high rate star formation. The gas supply that feeds the star birth will only last for another billion years or so.