It is the periodic comet with the shortest period known so far. It makes a turn around the Sun every 3.3 years (3 years and 106 days), with a perihelion (point closest to the Sun) around 51 million km. and an aphelion (most distant point of the Sun) of approximately 611 million km. This means that the comet approaches the Sun almost as much as Mercury and moves away from it almost like Jupiter.
Encke's comet belongs to the so-called "Jupiter's family": that large group of short-period comets (about 1 week), whose orbits are highly influenced by the passage near Jupiter. These, in past times, have experienced a phenomenon called capture by the giant planet of the solar system, which links them thus dragging the aphelion to the vicinity of its orbit.
The Encke is an astronomical element of great interest for various reasons. It has been noted, over the years, a progressive reduction in the ability to surround themselves with hair and tail: a sign that repeated steps along the Sun have been stripping it, little by little, of volatile elements, reducing it to a preponderantly rocky and inert nucleus. For this reason, some astronomers believe that the Encke represents the final state of that process that would lead new comets to transform, over time, into Apollo-type asteroids.
According to Czechoslovak astronomer Lubor Kresak, a fragment separated from the Encke and entered the Earth's atmosphere on June 30, 1908, falling into the Siberian highlands along the Middle Tunguska River, causing the destruction of 2,000 km. squares of forest and an explosion comparable to 20,000 tons of trilite. The small fragments of dust that then separated from the Encke have been considered responsible for the annual rain of shooting stars, called Táuridas, which reaches the maximum intensity on November 13 of each year.
This important comet has been known since relatively recent times. It was first observed by the French Mechain and Messier in 1786 and successively lost sight of. In 1818 he was observed again by Pons and then Johan Encke calculated his orbital elements, realizing that it was the same comet that appeared earlier.
|◄ Previous||Next ►|
|Enceladus||Encke (Division of)|