What defines a long-period comet in terms of its orbital duration?

Answer

An orbit taking thousands or even millions of years to complete.

Long-period comets are defined by their extremely long journeys around the Sun, requiring periods measured in thousands or millions of years to finish one revolution.

What defines a long-period comet in terms of its orbital duration?

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Seeing the Oort Cloud, Rogue Planet Nearby, Knocking ... - YouTube

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