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30-595: The Tarantula Nebula was observed by Nicolas-Louis de Lacaille during an expedition to the Cape of Good Hope between 1751 and 1753. He catalogued it as the second of the " Nebulae of the First Class ", "Nebulosities not accompanied by any star visible in the telescope of two feet". It was described as a diffuse nebula 20' across. Johann Bode included the Tarantula in his 1801 Uranographia star atlas and listed it in

60-502: A globular cluster in the future. In addition to NGC 2070, the Tarantula Nebula contains a number of other star clusters including the much older Hodge 301 . The most massive stars of Hodge 301 have already exploded in supernovae . The closest supernova observed since the invention of the telescope , Supernova 1987A , occurred in the outskirts of the Tarantula Nebula. There is a prominent supernova remnant enclosing

90-421: A table of eclipses for 1800 years. Lalande said of him that, during a comparatively short life, he had made more observations and calculations than all the astronomers of his time put together. The quality of his work rivalled its quantity, while the disinterestedness and rectitude of his moral character earned him universal respect. On his return to Paris in 1754, following a diversion to Mauritius , Lacaille

120-535: Is capitalised: CMa for Canis Major , CMi for Canis Minor . Two cases are ambiguous: Leo for the constellation Leo could be mistaken for Leo Minor (abbreviated LMi ), and Tri for Triangulum could be mistaken for Triangulum Australe (abbreviated TrA ). In addition to the three-letter abbreviations used today, the IAU also introduced four-letter abbreviations in 1932. The four-letter abbreviations were repealed in 1955 and are now obsolete, but were included in

150-473: Is now generally treated as referring to the whole nebula area of the Tarantula Nebula. The Tarantula Nebula has an apparent magnitude of 8. Considering its distance of about 49 kpc (160,000 light-years ), this is an extremely luminous non-stellar object. Its luminosity is so great that if it were as close to Earth as the Orion Nebula , the Tarantula Nebula would cast visible shadows . In fact, it

180-556: Is the most active starburst region known in the Local Group of galaxies . It is also one of the largest H II regions in the Local Group with an estimated diameter around 200 to 570 pc (650 to 1860 light years), and also because of its very large size, it is sometimes described as the largest, although other H II regions such as NGC 604 , which is in the Triangulum Galaxy , could be larger. The nebula resides on

210-553: The Collège de Lisieux and then theology at the Collège de Navarre . He was left destitute in 1731 by the death of his father, who had held a post in the household of the duchess of Vendôme. However, he was supported in his studies by the Duc de Bourbon , his father's former patron. After he graduated, he did not accept ordination as a priest but took deacon 's orders, becoming an Abbé . He concentrated thereafter on science, and, through

240-639: The French Revolution . His desire to determine the distances of the planets trigonometrically, using the longest possible baseline, led him to propose, in 1750, an expedition to the Cape of Good Hope . This was officially sanctioned by Roland-Michel Barrin de La Galissonière . There, he constructed an observatory on the shore of Table Bay with the support of the Dutch Governor Ryk Tulbagh . The primary result of his two-year stay

270-644: The genitive form of the constellation name. As the genitive is similar to the base name, the majority of the abbreviations are just the first three letters of the constellation name: Ori for Orion/Orionis , Ara for Ara/Arae , and Com for Coma Berenices/Comae Berenices . In some cases, the abbreviation contains letters from the genitive not appearing in the base name (as in Hyi for Hydrus/Hydri , to avoid confusion with Hydra , abbreviated Hya ; and Sge for Sagitta/Sagittae , to avoid confusion with Sagittarius , abbreviated Sgr ). Some abbreviations use letters beyond

300-692: The open cluster NGC 2060 , but the remnants of many other supernovae are difficult to detect in the complex nebulosity. An x-ray quiet black hole was discovered in the Tarantula Nebula, the first outside of the Milky Way Galaxy that does not radiate strongly. The black hole has a mass of at least 9 solar masses and is in a circular orbit with its 25 solar mass blue giant companion VFTS 243 . Nicolas-Louis de Lacaille Abbé Nicolas-Louis de Lacaille ( French: [nikɔla lwi də lakaj] ; 15 March 1713 – 21 March 1762), formerly sometimes spelled de la Caille ,

330-557: The radius of the Earth in the southern hemisphere. He set out a baseline in the Swartland plain north of present-day Darling . Using triangulation he then measured a 137 km arc of meridian between Cape Town and Aurora , determining the astronomical latitudes of the end points by means of astronomical-geodetic observations. There is a memorial to his work at a location near Aurora, pictured here. His result suggested that

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360-668: The 88 constellations so that every point in the sky belonged to one constellation. Some constellations are no longer recognized by the IAU, but may appear in older star charts and other references. Most notable is Argo Navis , which was one of Ptolemy's original 48 constellations. In the 1750s the French astronomer Nicolas Louis de Lacaille divided this into three separate constellations: Carina , Puppis , and Vela . The 88 constellations depict 42 animals, 29 inanimate objects, and 17 humans or mythological characters. Each IAU constellation has an official three-letter abbreviation based on

390-538: The Earth was more flattened towards the south pole than towards the north. George Everest , of the Indian Survey , while recuperating from an illness at the Cape nearly seventy years later, suggested that Lacaille's latitude observations had been affected by the deflection of the vertical , caused by gravitational attraction of Table Mountain at the southern end and by the Piketberg Mountain at

420-588: The NASA Dictionary of Technical Terms for Aerospace Use (NASA SP-7) published in 1965. These are labeled "NASA" in the table below and are included here for reference only. For help with the literary English pronunciations, see the pronunciation key . There is considerable diversity in how Latinate names are pronounced in English. For traditions closer to the original, see Latin spelling and pronunciation . Various other unofficial patterns exist alongside

450-709: The Royal Academy of Sciences, summarised the improvements to astronomy that had occurred during his lifetime, to which he had made no small contribution. His death, probably caused in part by over-work, occurred in 1762. He was buried in the vaults of the Mazarin College, now the Institut de France in Paris. In 1754, he was elected a foreign member of the Royal Swedish Academy of Sciences . He

480-434: The accompanying Allgemeine Beschreibung und Nachweisung der Gestirne catalogue as number 30 in the constellation "Xiphias or Dorado". Instead of being given a stellar magnitude, it was noted to be nebulous. The name Tarantula Nebula arose in the mid 20th century from its appearance in deep photographic exposures. 30 Doradus has often been treated as the designation of a star, or of the central star cluster NGC 2070 , but

510-614: The entire celestial sphere . Their boundaries were officially adopted by the International Astronomical Union in 1928 and published in 1930. The ancient Mesopotamians and later the Greeks established most of the northern constellations in international use today, listed by the Roman-Egyptian astronomer Ptolemy . The constellations along the ecliptic are called the zodiac . When explorers mapped

540-412: The initial three to unambiguously identify the constellation (for example when the name and its genitive differ in the first three letters): Aps for Apus/Apodis , CrA for Corona Australis , CrB for Corona Borealis , Crv for Corvus . ( Crater is abbreviated Crt to prevent confusion with CrA .) When letters are taken from the second word of a two-word name, the first letter from the second word

570-487: The leading edge of the LMC where ram pressure stripping, and the compression of the interstellar medium likely resulting from this, is at a maximum. 30 Doradus has at its centre the star cluster NGC 2070 which includes the compact concentration of stars known as R136 that produces most of the energy that makes the nebula visible. The estimated mass of the cluster is 450,000 solar masses , suggesting it will likely become

600-531: The northern. In 1838, Thomas Maclear , who was Astronomer Royal at the Cape, repeated the measurements over a longer baseline ( Maclear's arc measurement ) and ultimately confirmed Everest's conjecture. Maclear's Beacon was erected on the Table Mountain in Cape Town to help with the verification. During his voyage to the southern hemisphere as a passenger on the vessel Le Glorieux , captained by

630-567: The noted hydrographer Jean-Baptiste d'Après de Mannevillette, Lacaille became conscious of the difficulties in determining positions at sea. On his return to Paris he prepared the first set of tables of the Moon's position that was accurate enough to use for determining time and longitude by the method of 'Lunars' ( Lunar distances ) using the orbital theory of Clairaut . Lacaille was in fact an indefatigable calculator. Apart from constructing astronomical ephemerides and mathematical tables, he calculated

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660-497: The patronage of Jacques Cassini , obtained employment, first in surveying the coast from Nantes to Bayonne , then, in 1739, in remeasuring the French meridian arc , for which he is honoured with a pyramid at Juvisy-sur-Orge . The success of this difficult operation, which occupied two years, and achieved the correction of the anomalous result published by Jacques Cassini in 1718, was mainly due to Lacaille's industry and skill. He

690-458: The stars of the southern skies, European astronomers proposed new constellations for that region, as well as ones to fill gaps between the traditional constellations. Because of their Roman and European origins, every constellation has a Latin name. In 1922, the International Astronomical Union adopted three-letter abbreviations for 89 constellations, the modern list of 88 plus Argo . After this, Eugène Joseph Delporte drew up boundaries for each of

720-546: Was a French astronomer and geodesist who named 14 out of the 88 constellations . From 1750 to 1754, he studied the sky at the Cape of Good Hope in present-day South Africa . Lacaille observed over 10,000 stars using a refracting telescope . Born at Rumigny in the Ardennes in eastern France, he attended school in Mantes-sur-Seine (now Mantes-la-Jolie ). Afterwards, he studied rhetoric and philosophy at

750-667: Was also an honorary member of the academies of Saint Petersburg and Berlin, the Royal Society of London and the Royal Society of Göttingen , and the Institute of Bologna. Lacaille has the honor of naming 14 different constellations : The crater " La Caille " on the Moon is named after him. Asteroid 9135 Lacaille (AKA 7609 P-L and 1994 EK6), discovered on 17 October 1960 by Cornelis Johannes van Houten , Ingrid van Houten-Groeneveld and Tom Gehrels at Palomar Observatory ,

780-611: Was also named after him. In honor of his contribution to the study of the southern hemisphere sky, a 60-cm telescope at Réunion Island will be named the Lacaille Telescope. IAU designated constellations In contemporary astronomy , 88 constellations are recognized by the International Astronomical Union (IAU). Each constellation is a region of the sky bordered by arcs of right ascension and declination , together covering

810-428: Was distressed to find himself an object of public attention. He resumed his work at the Mazarin College. In 1757 he published his Astronomiae Fundamenta Novissimus , containing a list of about 400 bright stars with positions corrected for aberration and nutation . He carried out calculations on comet orbits and was responsible for giving Halley's Comet its name. His last public lecture, given on 14 September 1761 at

840-471: Was published posthumously in 1763. He found it necessary to introduce 14 new constellations which have since become standard. One of these was Mons Mensae , the only constellation named after a terrestrial feature (the Table Mountain ). An 1890 study of this catalogue by B. A. Gould found a considerable number of errors. While at the Cape , Lacaille performed an arc measurement to determine

870-673: Was rewarded by admission to the Royal Academy of Sciences and appointment as Professor of mathematics in the Mazarin college of the University of Paris , where he constructed a small observatory fitted for his own use. He was the author of a number of influential textbooks and a firm advocate of Newtonian gravitational theory. His students included Antoine Lavoisier and Jean Sylvain Bailly , both of whom were later guillotined during

900-470: Was the observations of nearly 10,000 southern stars, the production of which required observing every night for over a year. In the course of his survey he took note of 42 nebulous objects. He also achieved his aim of determining the lunar and solar parallaxes ( Mars serving as an intermediary). This work required near-simultaneous observations from Europe which were carried out by Jérôme Lalande . His southern catalogue, called Coelum Australe Stelliferum ,

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