Long-Period Comets
Comets with orbital periods longer than ~200 years, arriving on nearly parabolic orbits from all directions.
Overview
Comets on enormous orbits reaching deep into the outer Solar System, arriving from the Oort cloud after millions of years — the source of most great comets.
Members
6 modelled members.
- Hale–BoppC/1995
The 'Great Comet of 1997', a long-period comet with an exceptionally large, active nucleus that remained visible to the naked eye for a record 18 months.
TypeLong-period cometDiscovered1995Great cometYes - HyakutakeC/1996
The 'Great Comet of 1996', which passed very close to Earth and displayed one of the longest comet tails ever recorded.
TypeLong-period cometDiscovered1996Great cometYes - McNaughtC/2006
The 'Great Comet of 2007', the brightest comet in decades, whose vast fanned dust tail was a spectacular sight from the Southern Hemisphere.
TypeLong-period cometDiscovered2006Great cometYes - NEOWISEC/2020
The brightest comet visible from the Northern Hemisphere since Hale–Bopp, a naked-eye spectacle in July 2020 discovered by the NEOWISE space telescope.
TypeLong-period cometDiscovered2020Great cometYes - Siding SpringC/2013
A long-period comet that made an exceptionally close pass of Mars in October 2014, observed up close by the fleet of Mars orbiters and rovers.
TypeLong-period cometDiscovered2013 - ThatcherC/1861
A long-period comet on a roughly 415-year orbit, the parent body of the Lyrid meteor shower seen each April.
TypeLong-period cometPeriod415 yrDiscovered1861
Knowledge connections
- Group includesComet Hale–Bopp
- Group includesComet Hyakutake
- Group includesComet NEOWISE
- Group includesMcNaught
- Group includesSiding Spring
- Group includesThatcher
- Associated withC/1980 E1 (Bowell)
- Associated withC/1999 S4 (LINEAR)
- Associated withC/2007 W1 (Boattini)
- Associated withC/2017 K2 (PANSTARRS)
Sources
The primary and reference sources this topic draws on.
- NASANational Aeronautics and Space Administration
Mission data, planetary science, space telescopes, and public-domain imagery.
Most NASA-produced imagery is in the public domain; individual items are checked for usage terms before publication.
- NASA JPLJet Propulsion Laboratory / Solar System Dynamics
Orbital data, ephemerides, and small-body parameters for planets, asteroids, and comets.