Great Comet of 1744
Encyclopedia
The Great Comet of 1744, whose official designation is C/1743 X1, and which is also known as Comet de Chéseaux or Comet Klinkenberg-Chéseaux, was a spectacular comet
that was observed during 1743 and 1744. It was discovered independently in late November 1743 by Jan de Munck, in the second week of December by Dirk Klinkenberg, and, four days later, by Jean-Philippe de Chéseaux
. It became visible with the naked eye for several months in 1744 and displayed dramatic and unusual effects in the sky. Its absolute magnitude
— or intrinsic brightness — of 0.5 was the sixth highest in recorded history. Its apparent magnitude
may have reached as high as -7, leading it to be classified among what are called the "Great Comet
s". This comet is noted especially for developing a 'fan' of six tails after reaching its perihelion.
, and was independently sighted on December 9, 1743 by Klinkenberg at Haarlem
, and by Chéseaux from the observatory at Lausanne
on December 13. Chéseaux said it lacked a tail and resembled a nebulous star of the third magnitude; he measured the coma
as five minutes across.
The comet brightened steadily as it approached perihelion. By February 18, 1744, it reportedly was as bright as the planet Venus
(with an apparent magnitude of -4.6) and at this time displayed a double tail.
s from the sun. At about this time it was bright enough to be observed in daylight with the naked eye. As it moved away from perihelion, a spectacular tail developed — extending well above the horizon while the comet's head remained invisible due to the morning twilight. In early March of 1744, Chéseaux and several other observers reported an extremely unusual phenomenon — a 'fan' of six separate tails rose above the horizon.
The tail structure was a puzzle to astronomer
s for many years. Although other comets had displayed multiple tails on occasion, the 1744 comet was unique by having six. It has been suggested that the 'fan' of tails was generated by as many as three active sources on the cometary nucleus
, exposed in turn to solar radiation as the nucleus rotated. It also has been proposed that the tail phenomenon was a very prominent example of the "dust striae" seen in the tails of some comets, such as Comet West
and C/2006 P1 (McNaught).
to see the comet, but it remained visible for observers in the southern hemisphere
, some of whom reported a tail length of approximately 90 degrees on March 18. The comet was not seen after April 22, 1744.
The comet also was noted in Chinese astronomical records
. Researchers have found that some of their observations describe audible sounds associated with the comet, which may, if true, have resulted from the interaction of particles with the Earth's magnetosphere
, as sometimes described for the aurora
.
Among those who saw the comet was the thirteen-year-old Charles Messier
, on whom it had a profound and inspirational effect. He went on to become a significant figure in astronomy
, and later discovered many comets during his observations.
Comet
A comet is an icy small Solar System body that, when close enough to the Sun, displays a visible coma and sometimes also a tail. These phenomena are both due to the effects of solar radiation and the solar wind upon the nucleus of the comet...
that was observed during 1743 and 1744. It was discovered independently in late November 1743 by Jan de Munck, in the second week of December by Dirk Klinkenberg, and, four days later, by Jean-Philippe de Chéseaux
Jean-Philippe de Cheseaux
Jean-Philippe Loys de Chéseaux was an astronomer from Lausanne in Switzerland. In 1746 he presented a list of nebulae, eight of which were his own new discoveries, to the Académie Française des Sciences. The list was noted privately by Le Gentil in 1759, but only made public in 1892 by Guillaume...
. It became visible with the naked eye for several months in 1744 and displayed dramatic and unusual effects in the sky. Its absolute magnitude
Absolute magnitude
Absolute magnitude is the measure of a celestial object's intrinsic brightness. it is also the apparent magnitude a star would have if it were 32.6 light years away from Earth...
— or intrinsic brightness — of 0.5 was the sixth highest in recorded history. Its apparent magnitude
Apparent magnitude
The apparent magnitude of a celestial body is a measure of its brightness as seen by an observer on Earth, adjusted to the value it would have in the absence of the atmosphere...
may have reached as high as -7, leading it to be classified among what are called the "Great Comet
Great comet
A Great Comet is a comet that becomes exceptionally bright. There is no official definition; often the term will be attached to comets that become bright enough to be noticed by casual observers who are not actively looking for them, and become well known outside the astronomical community. Great...
s". This comet is noted especially for developing a 'fan' of six tails after reaching its perihelion.
Discovery
The comet was discovered on November 29, 1743, by Jan de Munck at MiddelburgMiddelburg
Middelburg is a municipality and a city in the south-western Netherlands and the capital of the province of Zeeland. It is situated in the Midden-Zeeland region. It has a population of about 48,000.- History of Middelburg :...
, and was independently sighted on December 9, 1743 by Klinkenberg at Haarlem
Haarlem
Haarlem is a municipality and a city in the Netherlands. It is the capital of the province of North Holland, the northern half of Holland, which at one time was the most powerful of the seven provinces of the Dutch Republic...
, and by Chéseaux from the observatory at Lausanne
Lausanne
Lausanne is a city in Romandy, the French-speaking part of Switzerland, and is the capital of the canton of Vaud. The seat of the district of Lausanne, the city is situated on the shores of Lake Geneva . It faces the French town of Évian-les-Bains, with the Jura mountains to its north-west...
on December 13. Chéseaux said it lacked a tail and resembled a nebulous star of the third magnitude; he measured the coma
Coma (cometary)
frame|right|The [[153P/Ikeya-Zhang|comet Ikeya-Zhang]] exhibiting a bright, condensed coma In astronomy, a coma is the nebulous envelope around the nucleus of a comet. It is formed when the comet passes close to the Sun on its highly elliptical orbit; as the comet warms, parts of it sublimate...
as five minutes across.
The comet brightened steadily as it approached perihelion. By February 18, 1744, it reportedly was as bright as the planet Venus
Venus
Venus is the second planet from the Sun, orbiting it every 224.7 Earth days. The planet is named after Venus, the Roman goddess of love and beauty. After the Moon, it is the brightest natural object in the night sky, reaching an apparent magnitude of −4.6, bright enough to cast shadows...
(with an apparent magnitude of -4.6) and at this time displayed a double tail.
Perihelion, "six tails"
The comet reached perihelion about March 1, 1744, when it was 0.2 astronomical unitAstronomical unit
An astronomical unit is a unit of length equal to about or approximately the mean Earth–Sun distance....
s from the sun. At about this time it was bright enough to be observed in daylight with the naked eye. As it moved away from perihelion, a spectacular tail developed — extending well above the horizon while the comet's head remained invisible due to the morning twilight. In early March of 1744, Chéseaux and several other observers reported an extremely unusual phenomenon — a 'fan' of six separate tails rose above the horizon.
The tail structure was a puzzle to astronomer
Astronomer
An astronomer is a scientist who studies celestial bodies such as planets, stars and galaxies.Historically, astronomy was more concerned with the classification and description of phenomena in the sky, while astrophysics attempted to explain these phenomena and the differences between them using...
s for many years. Although other comets had displayed multiple tails on occasion, the 1744 comet was unique by having six. It has been suggested that the 'fan' of tails was generated by as many as three active sources on the cometary nucleus
Comet nucleus
The nucleus is the solid, central part of a comet, popularly termed a dirty snowball. A cometary nucleus is composed of rock, dust, and frozen gases. When heated by the Sun, the gases sublimate and produce an atmosphere surrounding the nucleus known as the coma...
, exposed in turn to solar radiation as the nucleus rotated. It also has been proposed that the tail phenomenon was a very prominent example of the "dust striae" seen in the tails of some comets, such as Comet West
Comet West
Comet West formally designated C/1975 V1, 1976 VI, and 1975n, was a spectacular comet, sometimes considered to qualify for the status of "great comet".- Discovery :...
and C/2006 P1 (McNaught).
Southern hemisphere and Asian observations
Chéseaux, on March 9, was the last known observer in the northern hemisphereNorthern Hemisphere
The Northern Hemisphere is the half of a planet that is north of its equator—the word hemisphere literally means “half sphere”. It is also that half of the celestial sphere north of the celestial equator...
to see the comet, but it remained visible for observers in the southern hemisphere
Southern Hemisphere
The Southern Hemisphere is the part of Earth that lies south of the equator. The word hemisphere literally means 'half ball' or "half sphere"...
, some of whom reported a tail length of approximately 90 degrees on March 18. The comet was not seen after April 22, 1744.
The comet also was noted in Chinese astronomical records
Chinese astronomy
Astronomy in China has a very long history, with historians considering that "they [the Chinese] were the most persistent and accurate observers of celestial phenomena anywhere in the world before the Arabs."...
. Researchers have found that some of their observations describe audible sounds associated with the comet, which may, if true, have resulted from the interaction of particles with the Earth's magnetosphere
Magnetosphere
A magnetosphere is formed when a stream of charged particles, such as the solar wind, interacts with and is deflected by the intrinsic magnetic field of a planet or similar body. Earth is surrounded by a magnetosphere, as are the other planets with intrinsic magnetic fields: Mercury, Jupiter,...
, as sometimes described for the aurora
Aurora (astronomy)
An aurora is a natural light display in the sky particularly in the high latitude regions, caused by the collision of energetic charged particles with atoms in the high altitude atmosphere...
.
Among those who saw the comet was the thirteen-year-old Charles Messier
Charles Messier
Charles Messier was a French astronomer most notable for publishing an astronomical catalogue consisting of deep sky objects such as nebulae and star clusters that came to be known as the 110 "Messier objects"...
, on whom it had a profound and inspirational effect. He went on to become a significant figure in astronomy
Astronomy
Astronomy is a natural science that deals with the study of celestial objects and phenomena that originate outside the atmosphere of Earth...
, and later discovered many comets during his observations.
External links
- Orbit Diagram, C/1743 X1 NASANASAThe National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
Jet Propulsion Laboratory