Usually containing billions of stars, you could call galaxies the "big show" of the universe.
To set image as wallpaper, click on thumbnail to bring up full size image in separate window, then right click on full size image to bring up a little menu, choose "Set as wallpaper..." from menu (in Internet Explorer). If you have a Windows 98 or later OS on your computer, you should be able to use the "stretch" option to compensate for the difference between your screen resolution size and the picture size, if one exists. Most pictures were kept at the largest reasonable resolution size to preserve the image quality.
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