This is the M101, a beautiful spiral galaxy that is found some 170,000 light years across. It is almost twice as big as our own Milky Way Galaxy. It is one of the last entries in Charles Messier’s famous catalog. It is also known as the Pinwheel Galaxy.
M101 was also one of the original spiral nebulae observed with Lord Rosse's large 19th century telescope, the Leviathan of Parsonstown. In contrast, this multiwavelength view of the large island universe is a composite of images recorded by space-based telescopes in the 21st century. Color coded from X-rays to infrared wavelengths (high to low energies), the image data was taken from the Chandra X-ray Observatory (purple), the Galaxy Evolution Explorer (blue), Hubble Space Telescope(yellow), and the Spitzer Space Telescope(red).
Breathtaking.
(Image Credit: NASA, ESA, CXC, JPL - Caltech, STScI)