Amateur and professional astronomers partnered to create
this stunning photo illustration of spiral galaxy M106, which is located 23.5 million light-years away. Astrophotographer Robert Gendler used data from the Hubble Space Telescope and combined it with ground-based observations to build the image. The ground-based observations included Gendler's own observations and and fellow astrophotographer Jay GaBany's observations. The ground-based observations helped fill in holes where no Hubble data existed.
M 106, also known as Messier 106, is interesting because it is appears to have four spiral arms. Astronomers say
the extra arms, which are made up of hot gas, are the indirect result of violent churning of matter around the galaxy's central black hole.
A zoomable image of the photo is available here
and a larger image can be found here
Photo: NASA, ESA, the Hubble Heritage Team (STScI/AURA), and R. Gendler (for the Hubble Heritage Team)