![]() Melotte 20, an open cluster in the constellation Perseus that was first catalogued by Philibert Jacques Melotte in 1915. | |
![]() | |
The Melotte catalogue is a catalogue of 245 star clusters compiled by British astronomer Philibert Jacques Melotte. It was published in 1915 as A Catalogue of Star Clusters shown on Franklin-Adams Chart Plates. [1] Catalogue objects are denoted by Melotte, e.g. "Melotte 20". Dated prefixes include as Mel + catalogue number, e.g. "Mel 20". [2]
The catalogue contains 161 open clusters, 81 globular clusters, two asterisms, and one galaxy.
There are some errors in Melotte's list:
Dorado is a constellation in the Southern Sky. It was named in the late 16th century and is now one of the 88 modern constellations. Its name refers to the dolphinfish, which is known as dorado in Spanish, although it has also been depicted as a swordfish. Dorado contains most of the Large Magellanic Cloud, the remainder being in the constellation Mensa. The South Ecliptic pole also lies within this constellation.
An open cluster is a type of star cluster made of tens to a few thousand stars that were formed from the same giant molecular cloud and have roughly the same age. More than 1,100 open clusters have been discovered within the Milky Way galaxy, and many more are thought to exist. They are loosely bound by mutual gravitational attraction and become disrupted by close encounters with other clusters and clouds of gas as they orbit the Galactic Center. This can result in a loss of cluster members through internal close encounters and a dispersion into the main body of the galaxy. Open clusters generally survive for a few hundred million years, with the most massive ones surviving for a few billion years. In contrast, the more massive globular clusters of stars exert a stronger gravitational attraction on their members, and can survive for longer. Open clusters have been found only in spiral and irregular galaxies, in which active star formation is occurring.
The New General Catalogue of Nebulae and Clusters of Stars is an astronomical catalogue of deep-sky objects compiled by John Louis Emil Dreyer in 1888. The NGC contains 7,840 objects, including galaxies, star clusters and emission nebulae. Dreyer published two supplements to the NGC in 1895 and 1908, known as the Index Catalogues, describing a further 5,386 astronomical objects. Thousands of these objects are best known by their NGC or IC numbers, which remain in widespread use.
Messier 13 or M13, also designated NGC 6205 and sometimes called the Great Globular Cluster in Hercules or the Hercules Globular Cluster, is a globular cluster of several hundred thousand stars in the constellation of Hercules.
Philibert Jacques Melotte was a British astronomer whose parents emigrated from Belgium.
Robert Julius Trumpler was a Swiss-American astronomer.
The Carina Nebula or Eta Carinae Nebula is a large, complex area of bright and dark nebulosity in the constellation Carina, located in the Carina–Sagittarius Arm of the Milky Way galaxy. The nebula is approximately 8,500 light-years (2,600 pc) from Earth.
NGC 6633 is a large bright open cluster in the constellation Ophiuchus. Discovered in 1745-46 by Philippe Loys de Chéseaux, it was independently rediscovered by Caroline Herschel in 1783 and included in her brother William's catalog as H VIII.72. Bright enough to be seen with the naked eye, the cluster is considered a fine object for binoculars or small telescopes.
NGC 6231 is an open cluster in the southern sky located half a degrees north of Zeta Scorpii. NGC 6231 is part of a swath of young, bluish stars in the constellation Scorpius known as the Scorpius OB1 association. The star Zeta1 is a member of this association, while its brighter apparent partner, Zeta2, is only 150 ly from Earth and so is not a member.
The Caldwell catalogue is an astronomical catalogue of 109 star clusters, nebulae, and galaxies for observation by amateur astronomers. The list was compiled by Patrick Moore as a complement to the Messier catalogue.
The Heart Nebula is an emission nebula, 7500 light years away from Earth and located in the Perseus Arm of the Galaxy in the constellation Cassiopeia. It was discovered by William Herschel on 3 November 1787. It displays glowing ionized hydrogen gas and darker dust lanes.
The Collinder catalogue is a catalogue of 471 open clusters compiled by Swedish astronomer Per Collinder. It was published in 1931 as an appendix to Collinder's paper On structural properties of open galactic clusters and their spatial distribution.
Carina OB1 is a giant OB association in the Carina Nebula, which is home to some of the most massive and luminous stars in the Milky Way Galaxy. It includes the young star clusters Collinder 228, NGC 3293, NGC 3324, IC 2581, Trumpler 14, Trumpler 15 and Trumpler 16, the last being the home of Eta Carinae. It also includes another massive and luminous star, HD 93129A. It is approximately 2,680 parsecs (8,700 ly) from Earth.
NGC 1980 is a young open cluster associated with an emission nebula in the constellation Orion. It was discovered by William Herschel on 31 January 1786. Its apparent size is 14 × 14 arc minutes and it is located around the star Iota Orionis on the southern tip of the Orion constellation.
NGC 1278 is an elliptical galaxy located about 230 million light-years away in the constellation Perseus. NGC 1278 was discovered by astronomer Heinrich d'Arrest on February 14, 1863. It was then rediscovered by astronomer Guillaume Bigourdan on October 22, 1884 and was later listed as IC 1907. NGC 1278 is a member of the Perseus Cluster and is a low-luminosity AGN (LLAGN).
NGC 957 is a loosely bound open cluster located in the constellation Perseus. It has an apparent magnitude of 7.6 and an approximate size of 11 arc-minutes. It is young at less than 11 million years old.
Melotte 186 is a large, loosely bound open cluster located in the constellation Ophiuchus. It has an apparent magnitude of 3.0 and an approximate size of 240 arc-minutes.