Astronomers must be able to refer to a given star or other celestial object after studying it. This can be done with the star coordinates or with a name. Our knowledge of the existence of the fainter stars in the optical sky derives from surveys of the sky, such as a series of large-area photographs or the counting rate data from an x-ray detector that scans the entire sky. Such surveys typically yield the celestial coordinate of each located object. Interesting objects of a given type that are found in such surveys can be plotted on maps of the sky (charts) or listed with positions and other information in printed catalogs.
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Compared to film cameras, digital cameras are easy to use, fun and extremely versatile. Every day there’s more features being designed. Whether you have the cheapest model or a high end model, digital cameras can do an endless number of things. Let’s look at how to get the most out of your digital camera.