A Cotton Candy Pinwheel Galaxy

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Just in time for summer, this image of the Pinwheel Galaxy (M101) looks as pretty as a child’s toy and as delectable as cotton candy. This beautiful image combines data in the infrared, visible, ultraviolet and X-rays from four of NASA’s space-based telescopes. It’s like seeing with a regular camera, an ultraviolet camera, night-vision goggles and X-ray vision, all at the same time.

But within this multi-spectral view, you can see both young and old stars distributed along M101’s tightly-wound spiral arms. Composite images like this allow astronomers to see how features in one part of the spectrum match up with those seen in other parts.

The Pinwheel Galaxy is in the constellation of Ursa Major (also known as the Big Dipper). It is about 70 percent larger than our own Milky Way Galaxy, with a diameter of about 170,000 light years, and sits at a distance of 21 million light years from Earth. This means that the light we’re seeing in this image left the Pinwheel Galaxy about 21 million years ago – many millions of years before humans ever walked the Earth.