![]() ![]() These numbers, of course, are expected to rise in the future, for instance in upcoming experiments such as ESA’s Euclid satellite ( ) and the Large Synoptic Survey Telescope ( ). More recent examples are often, though not always, considerably larger the features for modern catalogues are extracted automatically from image data obtained by highly sophisticated telescope instrumentation, and for the largest sky surveys can run to hundreds of columns such as the Sloan Digital Sky Survey, and/or the order of a billion rows such as the Gaia mission. ![]() An early example is the Catalog of Nebulae and Star Clusters published by Charles Messier in 1781, containing data in six columns for 103 celestial objects, each observed individually by eye. A catalogue is thus naturally represented as a table with a certain number of rows (one for each observed object) and columns (one for each feature).
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