Quoting WISE site where an annotated version of the image can be seen: "This is a mosaic of the images covering the entire sky as observed by the Wide-field Infrared Survey Explorer (WISE), part of its All-Sky Data Release. In this mosaic, the Milky Way Galaxy runs horizontally across this map. The Milky Way is shaped like a disk and the Solar System is located in that disk about two-thirds of the way out from the center.
[W]e see the Milky Way as a band running through the sky. As we look toward the center of the Galaxy we are looking through more of the disk than when we are looking at large angles away from the center, and you can see a noticeable increase in stars (colored blue-green) toward the center of the image. Three of the four wavelengths surveyed by WISE were used to create this image. The colors used in this image represent specific wavelengths of infrared light. Cyan (blue-green) represents light emitted predominantly from stars and galaxies at a wavelength of 3.4 microns. Green and red represent light mostly emitted by dust at 12 and 22 microns, respectively."
The size of the uploaded image is 190 megapixels. Original JPEG equirectangular image can be downloaded here.
Image Credit: NASA/JPL-Caltech/WISE Team (this image is in public domain).
I've prepared different version of the image to my blog at pallopanoraama.blogspot.com which contains overlaid info bubbles helping navigating the image and a visible light version of the sky for comparison.
Welcome to Earth! It's a planet having an iron core, with two-thirds of its surface covered by water. Earth orbits a local star called the Sun, the light of which generates the food supply for all the millions of species of life on earth. The dominant species on Earth is the human being, and you're one of the six billion of them! Humans have iron in their blood, and their bodies are composed of two-thirds water, just like the planet they live on. The physical composition of the Earth, its people and everything on it contains an electro-magnetic field which is not yet fully understood. Theories and legends about the origin of Earth, people and life itself abound, however they are not commonly discussed. The bulk of earth's people spend their time immersed in daily activities, leaving the big questions for later. "Who are we? Where did we come from? Where are we going? How will we get there?" Many religions and philosophies have attempted to answer these questions over the years, but so far none has given an answer that everyone on the planet can accept. In contrast to all the disagreement, the similarities among people on earth are far, far greater than any differences. Welcome again to Earth! Enjoy your stay, and try to stay calm.