The Pinwheel Galaxy

It’s one of the last entries in Charles Messier’s famous catalog, but M101 is definitely not one of the least. The galaxy is big—roughly 170,000 light-years across, almost twice the size of our own Milky Way Galaxy. This multiwavelength view is a composite of images recorded by space-based telescopes. Color coded from X-rays to infrared wavelengths (high to low energies), the image data was taken from the Chandra X-ray Observatory (x-rays, purple), the Galaxy Evolution Explorer (ultraviolet, blue), the Hubble Space Telescope (visible light, yellow), and the Spitzer Space Telescope (infrared, red). While the X-ray data shows the multimillion degree gas around M101’s exploded stars and neutron star and black hole binary star systems, the lower energy data shows the stars and dust that define M101’s grand spiral arms. Known as the Pinwheel Galaxy, M101 lies within the boundaries of the northern constellation Ursa Major. It’s about 25 million light-years away.

Image Credit: NASA

Swan’s Way

These filaments of gas and dust visible in ultraviolet light were heated by the shockwave from a supernova which is still spreading out from the original explosion. The supernova which occurred between 5,000 and 8,000 years ago would have been bright enough to be seen clearly from Earth with the naked eye.

This ultraviolet image of the Cygnus Loop Nebula was taken by NASA’s Galaxy Evolution Explorer. The Cygnus Loop extends across an area more than three times the size of the full moon in the night sky and is tucked next to one of the “wings” in the constellation of Cygnus the Swan.

Image Credit: NASA