Dorado (, ) is a
constellation
A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object.
The first constellati ...
in the
Southern Sky. It was named in the late 16th century and is now one of the
88 modern 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 the entire celestial sph ...
. Its name refers to the
mahi-mahi
The mahi-mahi ( ) or common dolphinfish (''Coryphaena hippurus'') is a surface-dwelling ray-finned fish found in off-shore temperate, tropical, and subtropical waters worldwide. It is also widely called dorado (not to be confused with '' Salmin ...
(''Coryphaena hippurus''), which is known as ''dorado'' ("golden") in
Spanish, although it has also been depicted as a
swordfish
The swordfish (''Xiphias gladius''), also known as the broadbill in some countries, are large, highly migratory predatory fish characterized by a long, flat, pointed bill. They are the sole member of the Family (biology), family Xiphiidae. They ...
. Dorado contains most of the
Large Magellanic Cloud
The Large Magellanic Cloud (LMC) is a dwarf galaxy and satellite galaxy of the Milky Way. At a distance of around , the LMC is the second- or third-closest galaxy to the Milky Way, after the Sagittarius Dwarf Spheroidal Galaxy, Sagittarius Dwarf ...
, the remainder being in the constellation
Mensa. The South
Ecliptic pole also lies within this constellation.
Even though the name Dorado is not
Latin
Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...
but Spanish, astronomers give it the Latin
genitive
In grammar, the genitive case ( abbreviated ) is the grammatical case that marks a word, usually a noun, as modifying another word, also usually a noun—thus indicating an attributive relationship of one noun to the other noun. A genitive can ...
form ''Doradus'' when naming its stars; it is treated (like the adjacent asterism
Argo Navis
Argo Navis (the Ship Argo), or simply Argo, is one of Ptolemy's 48 constellations, now a grouping of three IAU constellations. It is formerly a single large constellation in the southern sky. The genitive is "Argus Navis", abbreviated "Arg". ...
) as a feminine proper name of Greek origin ending in -ō (like ''Io'' or ''Callisto'' or ''Argo''), which have a genitive ending ''-ūs''.
History
Dorado was one of twelve constellations named by
Petrus Plancius
Petrus Plancius (; born Pieter Platevoet ; 1552 – 15 May 1622) was a Dutch- Flemish astronomer, cartographer and clergyman. Born, in Dranouter, now in Heuvelland, West Flanders, he studied theology in Germany and England. At the age of 24 ...
from the observations of
Pieter Dirkszoon Keyser
Pieter Dirkszoon Keyser (occasionally Petrus Theodorus; – 11 September 1596) was a Dutch navigator and celestial cartographer who mapped several constellations on the southern celestial hemisphere.
Voyages and star observation
Little is ...
and
Frederick de Houtman. It appeared:
* On a celestial globe published in 1597 (or 1598) in Amsterdam by Plancius with
Jodocus Hondius.
* First depiction in a celestial atlas, in
Johann Bayer's ''
Uranometria'' of 1603.
* In
Johannes Kepler
Johannes Kepler (27 December 1571 – 15 November 1630) was a German astronomer, mathematician, astrologer, Natural philosophy, natural philosopher and writer on music. He is a key figure in the 17th-century Scientific Revolution, best know ...
's edition of
Tycho Brahe
Tycho Brahe ( ; ; born Tyge Ottesen Brahe, ; 14 December 154624 October 1601), generally called Tycho for short, was a Danish astronomer of the Renaissance, known for his comprehensive and unprecedentedly accurate astronomical observations. He ...
's star list in the ''
Rudolphine Tables
The ''Rudolphine Tables'' () consist of a star catalogue and planetary tables published by Johannes Kepler in 1627, using observational data collected by Tycho Brahe (1546–1601). The tables are named in memory of Rudolf II, Holy Roman Emper ...
'' of 1627; this was the first time that it was given the alternative name Xiphias, the
swordfish
The swordfish (''Xiphias gladius''), also known as the broadbill in some countries, are large, highly migratory predatory fish characterized by a long, flat, pointed bill. They are the sole member of the Family (biology), family Xiphiidae. They ...
. The name Dorado ultimately became dominant and was adopted by the IAU.
Dorado represents a
dolphinfish
''Coryphaena'' is a genus of marine ray-finned fishes known as the dolphinfishes, and is currently the only known genus in the family Coryphaenidae. The generic name is from Greek κορυφή (''koryphē'', "crown, top") and -αινα (-''aina ...
; it has also been called the goldfish because Dorado are gold-colored.
Features
Stars
Alpha Doradus is a blue-white star of magnitude 3.3, 176 light-years from Earth. It is the brightest star in Dorado.
Beta Doradus is a notably bright
Cepheid variable
A Cepheid variable () is a type of variable star that pulsates radially, varying in both diameter and temperature. It changes in brightness, with a well-defined stable period (typically 1–100 days) and amplitude. Cepheids are important cosmi ...
star. It is a yellow-tinged supergiant star that has a minimum magnitude of 4.1 and a maximum magnitude of 3.5. One thousand and forty light-years from Earth, Beta Doradus has a period of 9 days and 20 hours.
R Doradus
R Doradus (HD 29712 or P Doradus) is a red giant variable star in the far-southern constellation Dorado, close to the border with Reticulum. Its distance from Earth is . Having a angular diameter, uniform disk diameter of , it is though ...
is one of the many
variable star
A variable star is a star whose brightness as seen from Earth (its apparent magnitude) changes systematically with time. This variation may be caused by a change in emitted light or by something partly blocking the light, so variable stars are ...
s in Dorado.
S Dor, 9.721
hypergiant
A hypergiant ( luminosity class 0 or Ia+) is a very rare type of star that has an extremely high luminosity, mass, size and mass loss because of its extreme stellar winds. The term ''hypergiant'' is defined as luminosity class 0 (zero) in the MK ...
in the
Large Magellanic Cloud
The Large Magellanic Cloud (LMC) is a dwarf galaxy and satellite galaxy of the Milky Way. At a distance of around , the LMC is the second- or third-closest galaxy to the Milky Way, after the Sagittarius Dwarf Spheroidal Galaxy, Sagittarius Dwarf ...
, is the prototype of
S Doradus variable stars. The variable star
R Doradus
R Doradus (HD 29712 or P Doradus) is a red giant variable star in the far-southern constellation Dorado, close to the border with Reticulum. Its distance from Earth is . Having a angular diameter, uniform disk diameter of , it is though ...
5.73 has the largest-known apparent size of any star other than the Sun.
Gamma Doradus is the prototype of the
Gamma Doradus variable stars.
Supernova 1987A was the closest supernova to occur since the invention of the telescope.
SNR 0509-67.5 is the remnant of an unusually energetic Type 1a supernova from about 400 years ago.
HE 0437-5439 is a
hypervelocity star escaping from the
Milky Way
The Milky Way or Milky Way Galaxy is the galaxy that includes the Solar System, with the name describing the #Appearance, galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars in other arms of the galax ...
/
Magellanic Cloud system.
Dorado is also the location of the South
Ecliptic pole, which lies near the fish's head. The pole was called "Polus Doradinalis" by
Philipp von Zesen, aka Caesius.
In early 2020, the exoplanet
TOI-700 d was discovered orbiting the star
TOI-700 in Dorado. This is the first
potentially Earth-like exoplanet to be discovered by the
Transiting Exoplanet Survey Satellite
Transiting Exoplanet Survey Satellite (TESS) is a space telescope for NASA's Explorer program, designed to search for exoplanets using the transit method in an area 400 times larger than that covered by the Kepler mission. It was launched on ...
.
Deep-sky objects
Because Dorado contains part of the
Large Magellanic Cloud
The Large Magellanic Cloud (LMC) is a dwarf galaxy and satellite galaxy of the Milky Way. At a distance of around , the LMC is the second- or third-closest galaxy to the Milky Way, after the Sagittarius Dwarf Spheroidal Galaxy, Sagittarius Dwarf ...
, it is rich in deep sky objects. The Large Magellanic Cloud, 25,000 light-years in diameter, is a
satellite galaxy
A satellite galaxy is a smaller companion galaxy that travels on bound orbits within the gravitational potential of a more massive and Luminosity, luminous host galaxy (also known as the primary galaxy). Satellite galaxies and their constituents ...
of the Milky Way Galaxy, located at a distance of 179,000 light-years. It has been deformed by its gravitational interactions with the larger Milky Way. In 1987, it became host to
SN 1987A, the first supernova of 1987 and the closest since 1604. This 25,000-light-year-wide galaxy contains over 10,000 million stars. All coordinates given are for Epoch
J2000.0
In astronomy, an epoch or reference epoch is a moment in time used as a reference point for some time-varying astronomical quantity. It is useful for the celestial coordinates or orbital elements of a celestial body, as they are subject to pe ...
.

*
N 180B is an
emission nebula
An emission nebula is a nebula formed of ionized gases that emit light of various wavelengths. The most common source of ionization is high-energy ultraviolet photons emitted from a nearby hot star. Among the several different types of emission n ...
located in the
Large Magellanic Cloud
The Large Magellanic Cloud (LMC) is a dwarf galaxy and satellite galaxy of the Milky Way. At a distance of around , the LMC is the second- or third-closest galaxy to the Milky Way, after the Sagittarius Dwarf Spheroidal Galaxy, Sagittarius Dwarf ...
.
*
NGC 1566 (
RA 04h 20m 00s
Dec -56° 56.3′) is a face-on spiral galaxy. It gives its name to the
NGC 1566 Group of galaxies.
*
NGC 1755 (RA 04h 55m 13s Dec -68° 12.2′) is a globular cluster.
*
NGC 1763 (RA 04h 56m 49s Dec -68° 24.5′) is a bright nebula associated with three type B stars.
*
NGC 1761 (RA 04h 56m 37s Dec -66° 28.4') is an open cluster.
*
NGC 1820 (RA 05h 04m 02s Dec -67° 15.9′) is an open cluster.
*
NGC 1850 (RA 05h 08m 44s Dec -68° 45.7′) is a globular cluster.
*
NGC 1854 (RA 05h 09m 19s Dec -68° 50.8′) is a globular cluster.
*
NGC 1869 (RA 05h 13m 56s Dec -67° 22.8′) is an open cluster.
*
NGC 1901 (RA 05h 18m 15s Dec -68° 26.2′) is an open cluster.
*
NGC 1910 (RA 05h 18m 43s Dec -69° 13.9′) is an open cluster.
*
NGC 1936 (RA 05h 22m 14s Dec -67° 58.7′) is a bright nebula and is one of four NGC objects in close proximity, the others being
NGC 1929,
NGC 1934 and
NGC 1935.
*
NGC 1978 (RA 05h 28m 36s Dec -66° 14.0′) is an open cluster.
*
NGC 2002 (RA 05h 30m 17s Dec -66° 53.1′) is an open cluster.
*
NGC 2014 (RA 05h 44m 12.7s Dec −67° 42′ 57″) is a red emission nebula.
*
NGC 2020 (RA 05h 44m 12.7s Dec −67° 42′ 57″) is an HII region surrounding a
Wolf–Rayet star
Wolf–Rayet stars, often abbreviated as WR stars, are a rare heterogeneous set of stars with unusual spectroscopy, spectra showing prominent broad emission lines of ionised helium and highly ionised nitrogen or carbon. The spectra indicate very ...
.
*
NGC 2027 (RA 05h 35m 00s Dec -66° 55.0′) is an open cluster.
*
NGC 2032 (RA 05h 35m 21s Dec -67° 34.1′; also known as "Seagull Nebula") is a nebula complex that contains four NGC designations:
NGC 2029, NGC 2032,
NGC 2035 and
NGC 2040.

*
NGC 2074 (RA 05h 39m 03.0s Dec −69° 29′ 54″) is an emission nebula.
*
NGC 2078 (RA 05h 39m 54s Dec −69° 44′ 54″) is an emission nebula.
*
NGC 2080, also called the "Ghost Head Nebula", is an emission nebula that is 50 light-years wide in the Large Magellanic Cloud. It is named for the two distinct white patches that it possesses, which are regions of recent
star formation
Star formation is the process by which dense regions within molecular clouds in interstellar space—sometimes referred to as "stellar nurseries" or "star-forming regions"—Jeans instability, collapse and form stars. As a branch of astronomy, sta ...
. The western portion is colored green from
doubly ionized oxygen, the southern portion is red from
hydrogen alpha emissions, and the center region is colored yellow from both oxygen and hydrogen emissions. The western white patch, A1, has one massive, recently formed star inside. The eastern patch, A2, has several stars hidden in its dust.
*
Tarantula Nebula
The Tarantula Nebula (also known as 30 Doradus) is a large H II region in the Large Magellanic Cloud (LMC), forming its south-east corner (from Earth, Earth's perspective).
Discovery
The Tarantula Nebula was observed by Nicolas-Louis de Lacaill ...
is in the Large Magellanic Cloud, named for its spiderlike shape. It is also designated 30 Doradus, as it is visible to the naked eye as a slightly out-of-focus star. Larger than any nebula in the Milky Way at 1,000 light-years in diameter, it is also brighter, because it is illuminated by the open star cluster
NGC 2070, which has at its center the star cluster
R136. The illuminating stars are
supergiant
Supergiants are among the most massive and most luminous stars. Supergiant stars occupy the top region of the Hertzsprung–Russell diagram, with absolute visual magnitudes between about −3 and −8. The temperatures of supergiant stars range ...
s.
*
NGC 2164 (RA 05h 58m 53s Dec -68° 30.9′) is a globular cluster.
*
N44 is a
superbubble in the Large Magellanic Cloud that is 1,000 light-years wide. Its overall structure is shaped by the 40 hot stars towards its center. Within the superbubble of N44 is a smaller bubble catalogued as N44F. It is approximately 35 light-years in diameter and is shaped by an incredibly hot star at its center, which has a
stellar wind
A stellar wind is a flow of gas ejected from the stellar atmosphere, upper atmosphere of a star. It is distinguished from the bipolar outflows characteristic of young stars by being less collimated, although stellar winds are not generally spheri ...
speed of 7 million kilometers per hour. N44F also features dust columns with probable
star formation
Star formation is the process by which dense regions within molecular clouds in interstellar space—sometimes referred to as "stellar nurseries" or "star-forming regions"—Jeans instability, collapse and form stars. As a branch of astronomy, sta ...
hidden inside.
Equivalents
In
Chinese astronomy
Astronomy in China has a long history stretching from the Shang dynasty, being refined over a period of more than 3,000 years. The Ancient China, ancient Chinese people have identified stars from 1300 BCE, as Chinese star names later categori ...
, the stars of Dorado are in two of
Xu Guangqi
Xu Guangqi or Hsü Kuang-ch'i (April 24, 1562– November 8, 1633), also known by his baptismal name Paul or Paul Siu, was a Chinese agronomist, astronomer, mathematician, scholar-bureaucrat, politician, and writer during the late Ming dynasty ...
's
Southern Asterisms (近南極星區, ''Jìnnánjíxīngōu''): the
White Patches Attached (夾白, ''Jiābái'') and the
Goldfish
The goldfish (''Carassius auratus'') is a freshwater fish in the family Cyprinidae of the order Cypriniformes. It is commonly kept as a pet in indoor aquariums, and is one of the most popular aquarium fish. Goldfish released into the w ...
(金魚, ''Jīnyú'').
[AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 27 日]
Namesakes
*
''Dorado ''(SS-248) and
''Dorado'' (SS-526), two United States Navy submarines, were named after the same sea creature as the constellation.
Gallery
NGC1706 - HST - Potw1943a.tif, NGC 1706 is a spiral galaxy, about 230 million light-years away.
See also
*
Dorado in Chinese astronomy
*
IAU-recognized constellations
References
;Notes
* The above deep sky objects appear in ''
Norton's Star Atlas'', 1973 edition.
* Co-ordinates are obtained fro
Uranometria Chart Indexan
Skyview
* Images of the deep sky objects described herein may be viewed a
Skyview
;Citations
Sources
*
*
External links
Peoria Astronomical Society - Dorado
{{DEFAULTSORT:Dorado
Southern constellations
Constellations listed by Petrus Plancius