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How are long-period comets classified according to their orbital periods?

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asteroid Ida and its satellite, Dactyl — Small body Asteroid Ida and its satellite, Dactyl, photographed by the Galileo spacecraft on August 28, 1993, from a distance of about 10,870 km (6,750 miles). Ida is about 56 km (35 miles) long and shows the irregular shape and impact craters characteristic of many asteroids. The Galileo image revealed that Ida is accompanied by a tiny companion about 1.5 km (1 mile) wide, the first proof that some asteroids have natural satellites.

In astronomy, comets are traditionally categorized into two primary dynamical groups based on their orbital periods:

Short-period comets: These have orbital periods of fewer than 200 years.12
Long-period comets: These are defined as having orbital periods longer than 200 years.12

Long-period comets are often referred to as "nearly isotropic comets" because they exhibit random orbital inclinations and can approach the planetary system from any direction. They originate from the Oort cloud, a vast region surrounding the solar system, and many possess very distant orbits with semimajor axes of approximately 25,000 astronomical units (AU) or more.1

In terms of formal nomenclature, the International Astronomical Union uses the designation "C/" to identify long-period comets, distinguishing them from periodic comets, which are marked with a "P/" designation. Additionally, astronomers may use the Tisserand parameter to classify these bodies; long-period comets typically have a Tisserand parameter value of less than 2.0.21