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Solar System Series

Comet 2P/Encke

The shortest-period bright comet — and the parent of the Taurids.

Author: Juan Carlos Euyoque Aguilera · October 7, 2026 · CC BY 4.0

Image of Comet 2P/Encke (NASA/JPL, public domain)
NASA/JPL illustration, public domain. Not to scale.
3.30 years
Orbital period
~4.8 km
Nucleus
0.046
Albedo
0.339 AU
Perihelion

2P/Encke orbits the Sun every 3.30 years: the shortest orbital period of any reasonably bright comet in the solar system. It is named for Johann Franz Encke, who computed its orbit in 1819 — although Pierre Méchain was the first to record it, in 1786.

It is an old, darkened comet — it reflects only 4.6% of sunlight — and it is the parent of the Taurid meteor showers, famous for their October and November fireballs. In 2002 NASA launched the CONTOUR mission to visit it up close; the spacecraft was lost before arriving. No probe has ever visited it.

Measured data [DATO]

DataValueStateSource
Orbital period3.30 years (3.304) — the shortest orbital period of any reasonably bright, well-known comet[DATO] observedNASA Science (2P/Encke)
NucleusMean diameter ~4.8 km (4.86 km); geometric albedo 0.046 (reflects only 4.6% of sunlight); rotation 11.083 hours[DATO] observedWikipedia (Comet Encke)
OrbitPerihelion 0.339 AU; aphelion 4.097 AU; eccentricity 0.847; inclination 11.34°[DATO] observedWikipedia (Comet Encke)
Discovery and orbit computationFirst recorded by Pierre Méchain on 17-Jan-1786. Johann Franz Encke linked the sightings of 1786, 1795, 1805 and 1818, computed the orbit, published it in 1819, and predicted the 1822 return[DATO] observedNASA Science (2P/Encke)
Associated meteor showersParent comet of the Northern and Southern Taurids (peak October–November, famous for fireballs) and the daytime Beta Taurids (June–July)[DATO] observedNASA Science (2P/Encke); StarWalk
CONTOUR missionNASA's CONTOUR launched 3-Jul-2002 (Delta II, Cape Canaveral); contact lost 15-Aug-2002 during the Star 30 motor burn; declared lost 20-Dec-2002. An Encke flyby at 100–160 km was planned for 12-Nov-2003. No spacecraft has ever visited Encke up close[DATO] observedNASA (informe de la junta de investigación del percance CONTOUR)
Perihelion datesLast perihelion 22-Oct-2023; next perihelion 10-Feb-2027[DATO] observedStarWalk
Taurid Complex / giant fragmented comet[HYPOTHESIS] The 'coherent catastrophism' hypothesis (Clube and Napier) proposes that Encke and the Taurid stream are the remains of a giant comet (~100 km) that broke apart ~20,000 years ago. Not a fact: a hypothesis, not developed here[MODELO] modeledNational Geographic (artículo sobre las Táuridas)

Truths [DATO]

  • [DATO] Orbital period of 3.30 years: the shortest among bright, well-known comets.
  • [DATO] Its nucleus is ~4.8 km across and reflects only 4.6% of the light it receives (albedo 0.046).
  • [DATO] It is not named for its discoverer: it is named for Johann Franz Encke, who computed its orbit (1819); the first to see it was Pierre Méchain (1786).
  • [DATO] It is the parent comet of the Northern and Southern Taurids (October–November), known for their fireballs, and of the Beta Taurids (June–July).
  • [DATO] NASA's CONTOUR mission was to fly by it in November 2003; the spacecraft was lost in August 2002. No spacecraft has visited it up close.
  • [DATO] Its next perihelion is on 10 February 2027 (the last was 22 October 2023).

Marked myths [MITO]

[MITO] Comet Encke is named after its discoverer.

It is named for Johann Franz Encke, who computed its orbit and predicted its 1822 return. The first to record it was Pierre Méchain, in 1786; it was also seen by Caroline Herschel (1795) and Jean-Louis Pons (1805, 1818) without being recognized as the same object.

Fuente: NASA Science: el cometa no lleva el nombre de su(s) descubridor(es), sino de Johann Franz Encke, quien calculó su órbita.

[MITO] Encke has the shortest orbital period of all comets.

It has the shortest period among reasonably bright, well-known comets. The faint main-belt comet 311P/PanSTARRS has a period of 3.2 years.

Fuente: Wikipedia (Comet Encke).

[MITO] The 1908 Tunguska explosion was caused by a fragment of Comet Encke.

That is a hypothesis proposed by Ľ. Kresák in 1978 and criticized by Z. Sekanina in 1983. The exact nature of the Tunguska object has never been determined; it is not an established fact that it was an Encke fragment.

Fuente: Hipótesis de Kresák (1978), crítica de Sekanina (1983); enciclopedia con el resumen del debate.

[MITO] A 'swarm' of giant Encke fragments is coming toward Earth (alarmist headlines, 2019).

In June 2019 Earth passed ~30 million km from the zone where the hypothetical Taurid swarm might be; astronomers used the pass to search for it with telescopes. The astronomical community has observed no concentrations of mountain-sized objects and rejects the catastrophic predictions.

Fuente: The Weather Network (búsqueda del enjambre, 2019); Phys.org (2024): la astronomía convencional rechaza las predicciones catastróficas al no haberse observado esas concentraciones.

Open questions [PREGUNTA]

  • [PREGUNTA] How large are the biggest fragments of the Taurid swarm, if it exists as such?
  • [PREGUNTA] Encke has been fading since 1786: how many more perihelia will it survive before going dark?
  • [PREGUNTA] Will any future mission achieve the close flyby that CONTOUR never managed?

The chain in brief

  1. [DATA] 1. Seen by one, computed by another: Pierre Méchain recorded it in 1786; Johann Franz Encke linked the sightings, computed the orbit, published it in 1819, and predicted the 1822 return. That is why it is named for the man who computed its orbit, not for its discoverer.
  2. [DATA] 2. The shortest period among bright comets: It orbits the Sun every 3.30 years: the shortest orbital period of any reasonably bright, well-known comet.
  3. [DATA] 3. Old and darkened: Its nucleus is ~4.8 km across and reflects only 4.6% of the light it receives (albedo 0.046); the comet has been fading since 1786.
  4. [DATA] 4. Parent of the Taurids: It is the parent comet of the Northern and Southern Taurids, famous for their October and November fireballs, and of the daytime Beta Taurids of June and July.
  5. [DISPUTED] 5. No one has visited it up close: NASA's CONTOUR mission was to fly by it in November 2003, and the spacecraft was lost in August 2002; how many more perihelia Encke will survive before going dark remains open.