Number of discovered long-period comets per year with a perihelion distance smaller than 4 AU and a total absolute magnitude smaller than 11 each year since 1900. The gray histogram corresponds to all the comets in the Horizon/JPL data base, whereas the black historgram shows only the new comets in the JPL sample (see text for details).
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
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