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Canopus is the brightest star in the southern
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 ...
of
Carina Carina may refer to: Places Australia * Carina, Queensland, a suburb in Brisbane * Carina Heights, Queensland, a suburb in Brisbane * Carina, Victoria, a locality in Mildura Serbia * Carina, Osečina, a village in the Kolubara District ...
and the second-brightest star in the
night sky The night sky is the nighttime appearance of celestial objects like stars, planets, and the Moon, which are visible in a clear sky between sunset and sunrise, when the Sun is below the horizon. Natural light sources in a night sky include moonlig ...
. It is also designated α Carinae, which is
romanized In linguistics, romanization is the conversion of text from a different writing system to the Roman (Latin) script, or a system for doing so. Methods of romanization include transliteration, for representing written text, and transcription, ...
(
transliterated Transliteration is a type of conversion of a text from one writing system, script to another that involves swapping Letter (alphabet), letters (thus ''wikt:trans-#Prefix, trans-'' + ''wikt:littera#Latin, liter-'') in predictable ways, such as ...
) to Alpha Carinae. With a
visual apparent magnitude Apparent magnitude () is a measure of the brightness of a star, astronomical object or other celestial objects like artificial satellites. Its value depends on its intrinsic luminosity, its distance, and any extinction of the object's light cau ...
of −0.74, it is outshone only by
Sirius Sirius is the brightest star in the night sky. Its name is derived from the Greek word (Latin script: ), meaning 'glowing' or 'scorching'. The star is designated  Canis Majoris, Latinized to Alpha Canis Majoris, and abbr ...
. Located around from the
Sun The Sun is the star at the centre of the Solar System. It is a massive, nearly perfect sphere of hot plasma, heated to incandescence by nuclear fusion reactions in its core, radiating the energy from its surface mainly as visible light a ...
, Canopus is a
bright giant A giant star has a substantially larger radius and luminosity than a main-sequence (or ''dwarf'') star of the same surface temperature. They lie above the main sequence (luminosity class V in the Yerkes spectral classification) on the Hertzspr ...
of spectral type A9, so it is essentially white when seen with the naked eye. It has a luminosity over 10,000 times the
luminosity of the Sun The solar luminosity () is a unit of radiant flux ( power emitted in the form of photons) conventionally used by astronomers to measure the luminosity of stars, galaxies and other celestial objects in terms of the output of the Sun. One nominal s ...
, is nine to ten times as massive, and has expanded to 71 times the
Sun's radius Solar radius is a unit of distance used to express the size of objects in astronomy relative to the Sun. The solar radius is usually defined as the radius to the layer in the Sun's photosphere where the optical depth equals 2/3: 1\,R_ = 6.957\ti ...
. Its enlarged
photosphere The photosphere is a star's outer shell from which light is radiated. It extends into a star's surface until the plasma becomes opaque, equivalent to an optical depth of approximately , or equivalently, a depth from which 50% of light will esc ...
has an
effective temperature The effective temperature of a body such as a star or planet is the temperature of a black body that would emit the same total amount of electromagnetic radiation. Effective temperature is often used as an estimate of a body's surface temperature ...
of around . Canopus is undergoing core
helium burning The triple-alpha process is a set of nuclear fusion reactions by which three helium-4 nuclei (alpha particles) are transformed into carbon. In stars Helium accumulates in the cores of stars as a result of the proton–proton chain reaction a ...
and is currently in the so-called
blue loop In the field of stellar evolution, a blue loop is a stage in the life of an evolved star where it changes from a cool star to a hotter one before cooling again. The name derives from the shape of the evolutionary track on a Hertzsprung–Russel ...
phase of its
evolution Evolution is the change in the heritable Phenotypic trait, characteristics of biological populations over successive generations. It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, re ...
, having already passed through the red-giant branch after exhausting the hydrogen in its core. Canopus is a source of X-rays, which are likely being emitted from its corona. The prominent appearance of Canopus means it has been the subject of mythological lore among many ancient peoples. Its proper name is generally considered to originate from the
mythological Myth is a genre of folklore consisting primarily of narratives that play a fundamental role in a society. For scholars, this is very different from the vernacular usage of the term "myth" that refers to a belief that is not true. Instead, the ...
Canopus Canopus is the brightest star in the southern constellation of Carina (constellation), Carina and the list of brightest stars, second-brightest star in the night sky. It is also Bayer designation, designated α Carinae, which is Rom ...
, who was a navigator for
Menelaus In Greek mythology, Menelaus (; ) was a Greek king of Mycenaean (pre- Dorian) Sparta. According to the ''Iliad'', the Trojan war began as a result of Menelaus's wife, Helen, fleeing to Troy with the Trojan prince Paris. Menelaus was a central ...
, king of
Sparta Sparta was a prominent city-state in Laconia in ancient Greece. In antiquity, the city-state was known as Lacedaemon (), while the name Sparta referred to its main settlement in the Evrotas Valley, valley of Evrotas (river), Evrotas rive ...
. The acronycal rising marked the date of the Ptolemaia festival in Egypt. In ancient India, it was named
Agastya Agastya was a revered Indian sage of Hinduism. In the Indian tradition, he is a noted recluse and an influential scholar in diverse languages of the Indian subcontinent. He is regarded in some traditions to be a Chiranjivi. He and his wife ...
after the revered
Vedic upright=1.2, The Vedas are ancient Sanskrit texts of Hinduism. Above: A page from the '' Atharvaveda''. The Vedas ( or ; ), sometimes collectively called the Veda, are a large body of religious texts originating in ancient India. Composed ...
sage. For Chinese astronomers, it was known as the Old Man of the South Pole. In
Islamic astronomy Medieval Islamic astronomy comprises the astronomical developments made in the Islamic world, particularly during the Islamic Golden Age (9th–13th centuries), and mostly written in the Arabic language. These developments mostly took place in th ...
, it is Suhail or Suhayl, a name that is also commonly used to imply rareness of appearance (as Canopus infrequently appeared to a gazer at Middle Eastern latitutes)


Nomenclature

The name ''Canopus'' is a Latinisation of the
Ancient Greek Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Greek ...
name Κάνωβος/Kanôbos, recorded in Claudius Ptolemy's ''
Almagest The ''Almagest'' ( ) is a 2nd-century Greek mathematics, mathematical and Greek astronomy, astronomical treatise on the apparent motions of the stars and planetary paths, written by Ptolemy, Claudius Ptolemy ( ) in Koine Greek. One of the most i ...
'' (c.150 AD). Eratosthenes used the same spelling. Hipparchos wrote it as Κάνωπος.
John Flamsteed John Flamsteed (19 August 1646 – 31 December 1719) was an English astronomer and the first Astronomer Royal. His main achievements were the preparation of a 3,000-star catalogue, ''Catalogus Britannicus'', and a star atlas called '' Atlas ...
wrote Canobus, as did
Edmond Halley Edmond (or Edmund) Halley (; – ) was an English astronomer, mathematician and physicist. He was the second Astronomer Royal in Britain, succeeding John Flamsteed in 1720. From an observatory he constructed on Saint Helena in 1676–77, Hal ...
in his 1679 ''Catalogus Stellarum Australium''. The name has two possible derivations, both listed in Richard Hinckley Allen's seminal '' Star Names: Their Lore and Meaning''. * The brightest star in the obsolete constellation of
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". ...
, which represented the ship used by
Jason Jason ( ; ) was an ancient Greek mythological hero and leader of the Argonauts, whose quest for the Golden Fleece is featured in Greek literature. He was the son of Aeson, the rightful king of Iolcos. He was married to the sorceress Med ...
and the
Argonauts The Argonauts ( ; ) were a band of heroes in Greek mythology, who in the years before the Trojan War (around 1300 BC) accompanied Jason to Colchis in his quest to find the Golden Fleece. Their name comes from their ship, ''Argo'', named after it ...
, was given the name of a ship's pilot from another Greek legend:
Canopus Canopus is the brightest star in the southern constellation of Carina (constellation), Carina and the list of brightest stars, second-brightest star in the night sky. It is also Bayer designation, designated α Carinae, which is Rom ...
, pilot of
Menelaus In Greek mythology, Menelaus (; ) was a Greek king of Mycenaean (pre- Dorian) Sparta. According to the ''Iliad'', the Trojan war began as a result of Menelaus's wife, Helen, fleeing to Troy with the Trojan prince Paris. Menelaus was a central ...
' ship on his quest to retrieve
Helen of Troy Helen (), also known as Helen of Troy, or Helen of Sparta, and in Latin as Helena, was a figure in Greek mythology said to have been the most beautiful woman in the world. She was believed to have been the daughter of Zeus and Leda (mythology), ...
after she was taken by
Paris Paris () is the Capital city, capital and List of communes in France with over 20,000 inhabitants, largest city of France. With an estimated population of 2,048,472 residents in January 2025 in an area of more than , Paris is the List of ci ...
. * A ruined ancient Egyptian port named
Canopus Canopus is the brightest star in the southern constellation of Carina (constellation), Carina and the list of brightest stars, second-brightest star in the night sky. It is also Bayer designation, designated α Carinae, which is Rom ...
lies near the mouth of the
Nile The Nile (also known as the Nile River or River Nile) is a major north-flowing river in northeastern Africa. It flows into the Mediterranean Sea. The Nile is the longest river in Africa. It has historically been considered the List of river sy ...
, site of the
Battle of the Nile The Battle of the Nile (also known as the Battle of Aboukir Bay; ) was fought between the Royal Navy and the French Navy at Abu Qir Bay, Aboukir Bay in Ottoman Egypt, Egypt between 1–3 August 1798. It was the climax of the Mediterranean ca ...
. It is speculated that its name is derived from the Egyptian Coptic ''Kahi Nub'' ("Golden Earth"), which refers to how Canopus would have appeared near the horizon in
ancient Egypt Ancient Egypt () was a cradle of civilization concentrated along the lower reaches of the Nile River in Northeast Africa. It emerged from prehistoric Egypt around 3150BC (according to conventional Egyptian chronology), when Upper and Lower E ...
, reddened by atmospheric extinction from that position. In 2016, the
International Astronomical Union The International Astronomical Union (IAU; , UAI) is an international non-governmental organization (INGO) with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreach, education, and developmen ...
organized a
Working Group on Star Names The International Astronomical Union (IAU) established a Working Group on Star Names (WGSN) in May 2016 to catalog and standardize proper names for stars for the international astronomical community. It operates under Division C – Education ...
(WGSN) to catalog and standardize proper names for stars. The WGSN's first bulletin of July 2016 included a table of the first two batches of names approved by the WGSN, which included ''Canopus'' for this star. Canopus is now included in the ''IAU Catalog of Star Names''. Canopus traditionally marked the steering oar of the ship
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". ...
. German celestial cartographer Johann Bayer gave it—as the brightest star in the constellation—the designation of ''α Argus'' ( Latinised to ''Alpha Argus'') in 1603. In 1763, French astronomer Nicolas Louis de Lacaille divided the huge constellation into three smaller ones, and hence Canopus became ''α Carinae'' ( Latinised to ''Alpha Carinae''). It is listed in the
Bright Star Catalogue The Bright Star Catalogue, also known as the Yale Catalogue of Bright Stars, Yale Bright Star Catalogue, or just YBS, is a star catalogue that lists all stars of stellar magnitude 6.5 or brighter, which is roughly every star visible to the na ...
as HR 2326, the
Henry Draper Catalogue The ''Henry Draper Catalogue'' (HD) is an astronomical star catalogue published between 1918 and 1924, giving spectroscopic classifications for 225,300 stars; it was later expanded by the ''Henry Draper Extension'' (HDE), published between 192 ...
as HD 45348, and the
Hipparcos catalogue ''Hipparcos'' was a scientific satellite of the European Space Agency (ESA), launched in 1989 and operated until 1993. It was the first space experiment devoted to precision astrometry, the accurate measurement of the positions and distances of ...
as HIP 30438. Flamsteed did not number this southern star, but Benjamin Apthorp Gould gave it the number 7 (7 G. Carinae) in his ''Uranometria Argentina''. An occasional name seen in English is ''Soheil'', or the feminine Soheila; in Turkish is ''Süheyl'', or the feminine Süheyla, from the Arabic name for several bright stars, سهيل ''suhayl'', and Canopus was known as Suhel in medieval times. Alternative spellings include Suhail, Souhail, Suhilon, Suheyl, Sohayl, Sohail, Suhayil, Shoel, Sohil, Soheil, Sahil, Suhayeel, Sohayil, Sihel, and Sihil. An alternative name was ''Wazn'' "weight" or ''Haḍar'' "ground" , implying the anchor stone used by ship, rather than being related to its low position near the horizon. Hence comes its name in the '' Alfonsine tables'', Suhel ponderosus, a Latinization of ''Al Suhayl al Wazn''. Its Greek name was revived during the
Renaissance The Renaissance ( , ) is a Periodization, period of history and a European cultural movement covering the 15th and 16th centuries. It marked the transition from the Middle Ages to modernity and was characterized by an effort to revive and sur ...
.


Observation

The Muslim astronomer
Ibn Rushd Ibn Rushd (14 April 112611 December 1198), archaically Latinized as Averroes, was an Arab Muslim polymath and jurist from Al-Andalus who wrote about many subjects, including philosophy, theology, medicine, astronomy, physics, psychology, math ...
went to
Marrakesh Marrakesh or Marrakech (; , ) is the fourth-largest city in Morocco. It is one of the four imperial cities of Morocco and is the capital of the Marrakesh–Safi Regions of Morocco, region. The city lies west of the foothills of the Atlas Mounta ...
(in Morocco) to observe the star in 1153, as it was invisible in his native Córdoba,
Al-Andalus Al-Andalus () was the Muslim-ruled area of the Iberian Peninsula. The name refers to the different Muslim states that controlled these territories at various times between 711 and 1492. At its greatest geographical extent, it occupied most o ...
. He used the different visibility in different latitudes to argue that the Earth is round, following Aristotle's argument which held that such an observation was only possible if the Earth was a relatively small sphere. English explorer Robert Hues brought Canopus to the attention of European observers in his 1592 work ''Tractatus de Globis'', along with
Achernar Achernar is the brightest star in the constellation of Eridanus and the ninth-brightest in the night sky. It has the Bayer designation Alpha Eridani, which is Latinized from α Eridani and abbreviated Alpha Eri or α Eri. The name Ac ...
and
Alpha Centauri Alpha Centauri (, α Cen, or Alpha Cen) is a star system in the southern constellation of Centaurus (constellation), Centaurus. It consists of three stars: Rigil Kentaurus (), Toliman (), and Proxima Centauri (). Proxima Centauri ...
, noting:
"Now, therefore, there are but three Stars of the first magnitude that I could perceive in all those parts which are never seene here in England. The first of these is that bright Star in the sterne of
Argo In Greek mythology, the ''Argo'' ( ; ) was the ship of Jason and the Argonauts. The ship was built with divine aid, and some ancient sources describe her as the first ship to sail the seas. The ''Argo'' carried the Argonauts on their quest fo ...
which they call Canobus. The second is in the end of Eridanus. The third is in the right foote of the Centaure."
In the Southern Hemisphere, Canopus and
Sirius Sirius is the brightest star in the night sky. Its name is derived from the Greek word (Latin script: ), meaning 'glowing' or 'scorching'. The star is designated  Canis Majoris, Latinized to Alpha Canis Majoris, and abbr ...
are both visible high in the sky simultaneously, and reach a meridian just apart. Brighter than first magnitude, Canopus can be seen by naked eye in the early twilight. Mostly visible in mid to late summer in the Southern Hemisphere, Canopus culminates at midnight on December 27, and at 9 PM on February 11.Schaaf, p. 257. When seen from latitudes south of  S, Canopus is a
circumpolar star A circumpolar star is a star that, as viewed from a given latitude on Earth, never sets below the horizon due to its apparent proximity to one of the celestial poles. Circumpolar stars are therefore visible from said location toward the nearest p ...
. Since Canopus is so far south in the sky, it never rises in mid- to far-northern latitudes; in theory the northern limit of visibility is latitude north. This is just south of
Athens Athens ( ) is the Capital city, capital and List of cities and towns in Greece, largest city of Greece. A significant coastal urban area in the Mediterranean, Athens is also the capital of the Attica (region), Attica region and is the southe ...
,
San Francisco San Francisco, officially the City and County of San Francisco, is a commercial, Financial District, San Francisco, financial, and Culture of San Francisco, cultural center of Northern California. With a population of 827,526 residents as of ...
, and
Seoul Seoul, officially Seoul Special Metropolitan City, is the capital city, capital and largest city of South Korea. The broader Seoul Metropolitan Area, encompassing Seoul, Gyeonggi Province and Incheon, emerged as the world's List of cities b ...
, and very close to
Seville Seville ( ; , ) is the capital and largest city of the Spain, Spanish autonomous communities of Spain, autonomous community of Andalusia and the province of Seville. It is situated on the lower reaches of the Guadalquivir, River Guadalquivir, ...
and
Agrigento Agrigento (; or ) is a city on the southern coast of Sicily, Italy and capital of the province of Agrigento. Founded around 582 BC by Greek colonists from Gela, Agrigento, then known as Akragas, was one of the leading cities during the golden ...
. It is almost exactly the latitude of
Lick Observatory The Lick Observatory is an astronomical observatory owned and operated by the University of California. It is on the summit of Mount Hamilton (California), Mount Hamilton, in the Diablo Range just east of San Jose, California, United States. The ...
on Mt. Hamilton, California, from which it is readily visible because of the effects of elevation and
atmospheric refraction Atmospheric refraction is the deviation of light or other electromagnetic wave from a straight line as it passes through the atmosphere due to the variation in air density as a function of height. This refraction is due to the velocity of light ...
, which add another degree to its apparent altitude. Under ideal conditions, it can be spotted as far north as latitude from the Pacific coast. Another northernmost record of visibility came from
Mount Nemrut Mount Nemrut or Nemrud (; ; ; Greek language, Greek: Όρος Νεμρούτ) is a mountain in southeastern Turkey, notable for the summit where a number of large statues are erected around what is assumed to be a royal tomb from the 1st century ...
in Turkey, latitude . It is more easily visible in places such as the Gulf Coast and Florida, and the island of
Crete Crete ( ; , Modern Greek, Modern: , Ancient Greek, Ancient: ) is the largest and most populous of the Greek islands, the List of islands by area, 88th largest island in the world and the List of islands in the Mediterranean#By area, fifth la ...
(Greece) where the best season for viewing it around 9 p.m. is during late January and early February. Canopus has a B–V
color index In astronomy, the color index is a simple numerical expression that determines the color of an object, which in the case of a star gives its temperature. The lower the color index, the more blue (or hotter) the object is. Conversely, the larg ...
of +0.15—where 0 is a blue-white—indicating it is essentially white, although it has been described as yellow-white. Canopus' spectral type has been given as F0 and the incrementally warmer A9. It is less yellow than
Altair Altair is the brightest star in the constellation of Aquila (constellation), Aquila and the list of brightest stars, twelfth-brightest star in the night sky. It has the Bayer designation Alpha Aquilae, which is Latinisation of name ...
or
Procyon Procyon () is the brightest star in the constellation of Canis Minor and usually the list of brightest stars, eighth-brightest star in the night sky, with an apparent visual magnitude of 0.34. It has the Bayer designation α Canis Min ...
, with indices measured as 0.22 and 0.42, respectively. Some observers may have perceived Canopus as yellow-tinged because it is low in the sky and hence subject to atmospheric effects.Schaaf, pp. 112–13.
Patrick Moore Sir Patrick Alfred Caldwell-Moore (; 4 March 1923 – 9 December 2012) was an English amateur astronomer who attained prominence in that field as a writer, researcher, radio commentator and television presenter. Moore's early interest in astro ...
said that it never appeared anything but white to him. The
bolometric correction In astronomy, the bolometric correction is the correction made to the absolute magnitude of an object in order to convert its visible magnitude to its bolometric magnitude. It is large for stars which radiate most of their energy outside of the v ...
for Canopus is 0.00, indicating that the visual absolute magnitude and bolometric absolute magnitude are equal. Canopus was previously proposed to be a member of the Scorpius–Centaurus association, however it is not located near the subgroups of that association, and has not been included as a Sco-Cen member in kinematic studies that used
Hipparcos ''Hipparcos'' was a scientific satellite of the European Space Agency (ESA), launched in 1989 and operated until 1993. It was the first space experiment devoted to precision astrometry, the accurate measurement of the positions and distances of ...
astrometric data. Canopus is not thought to be a member of any nearby young stellar groups. In 2014, astronomer Eric Mamajek reported that an extremely magnetically active M dwarf (having strong coronal X-ray emission), 1.16 degrees south of Canopus, appears to share a
common proper motion This glossary of astronomy is a list of definitions of terms and concepts relevant to astronomy and cosmology, their sub-disciplines, and related fields. Astronomy is concerned with the study of astronomical object, celestial objects and phenomena ...
with Canopus. The projected separation of the M dwarf 2MASS J06234738-5351131 ("Canopus B") is approximately 1.9 parsecs. However, despite this large separation, it is still within the estimated tidal radius (2.9 parsecs) for the massive star Canopus. Since it is more luminous than any star closer to Earth, Canopus has been the brightest star in the night sky during three epochs over the past four million years. Other stars appear brighter only during relatively temporary periods, during which they are passing the Solar System much closer than Canopus. About 90,000 years ago,
Sirius Sirius is the brightest star in the night sky. Its name is derived from the Greek word (Latin script: ), meaning 'glowing' or 'scorching'. The star is designated  Canis Majoris, Latinized to Alpha Canis Majoris, and abbr ...
moved close enough that it became brighter than Canopus, and that will remain so for another 210,000 years. But in 480,000 years, as Sirius moves further away and appears fainter, Canopus will once again be the brightest, and will remain so for a period of about 510,000 years.


Role in navigation

The southeastern wall of the
Kaaba The Kaaba (), also spelled Kaba, Kabah or Kabah, sometimes referred to as al-Kaba al-Musharrafa (), is a stone building at the center of Islam's most important mosque and Holiest sites in Islam, holiest site, the Masjid al-Haram in Mecca, Sa ...
in
Mecca Mecca, officially Makkah al-Mukarramah, is the capital of Mecca Province in the Hejaz region of western Saudi Arabia; it is the Holiest sites in Islam, holiest city in Islam. It is inland from Jeddah on the Red Sea, in a narrow valley above ...
is aligned with the rising point of Canopus, and is also named ''Janūb''. The
Bedouin The Bedouin, Beduin, or Bedu ( ; , singular ) are pastorally nomadic Arab tribes who have historically inhabited the desert regions in the Arabian Peninsula, North Africa, the Levant, and Mesopotamia (Iraq). The Bedouin originated in the Sy ...
people of the
Negev The Negev ( ; ) or Naqab (), is a desert and semidesert region of southern Israel. The region's largest city and administrative capital is Beersheba (pop. ), in the north. At its southern end is the Gulf of Aqaba and the resort town, resort city ...
and Sinai knew Canopus as ''Suhayl'', and used it and
Polaris Polaris is a star in the northern circumpolar constellation of Ursa Minor. It is designated α Ursae Minoris (Latinisation of names, Latinized to ''Alpha Ursae Minoris'') and is commonly called the North Star or Pole Star. With an ...
as the two principal stars for navigation at night. Because it disappears below the horizon in those regions, it became associated with a changeable nature, as opposed to always-visible Polaris, which was circumpolar and hence 'steadfast'. The south
celestial pole The north and south celestial poles are the two points in the sky where Earth's axis of rotation, indefinitely extended, intersects the celestial sphere. The north and south celestial poles appear permanently directly overhead to observers at ...
can be approximately located using Canopus and two different bright stars. The first,
Achernar Achernar is the brightest star in the constellation of Eridanus and the ninth-brightest in the night sky. It has the Bayer designation Alpha Eridani, which is Latinized from α Eridani and abbreviated Alpha Eri or α Eri. The name Ac ...
, makes an
equilateral triangle An equilateral triangle is a triangle in which all three sides have the same length, and all three angles are equal. Because of these properties, the equilateral triangle is a regular polygon, occasionally known as the regular triangle. It is the ...
between the stars and the south pole. One can also locate the pole more roughly using an imaginary line between Sirius and Canopus; Canopus will be approximately at the midpoint, being one way to Sirius and to the pole. Canopus's brightness and location well off the
ecliptic The ecliptic or ecliptic plane is the orbital plane of Earth's orbit, Earth around the Sun. It was a central concept in a number of ancient sciences, providing the framework for key measurements in astronomy, astrology and calendar-making. Fr ...
make it useful for space navigation. Many spacecraft carry a special camera known as a "Canopus
Star Tracker A star tracker is an optical device that measures the positions of stars using photocells or a camera. As the positions of many stars have been measured by astronomers to a high degree of accuracy, a star tracker on a satellite or spacecraft may ...
" plus a Sun sensor for
attitude Attitude or Attitude may refer to: Philosophy and psychology * Attitude (psychology), a disposition or state of mind ** Attitude change * Propositional attitude, a mental state held towards a proposition Science and technology * Orientation ...
determination.
Mariner 4 Mariner 4 (Mariner C-3, together with Mariner 3 known as Mariner-Mars 1964) was the Mariner program, fourth in a series of spacecraft intended for planetary exploration in a flyby mode. It was designed to conduct closeup scientific observations ...
used Canopus for second axis stabilisation (after locking on the Sun) in 1964, the first time a star had been used.


Spectrum

Canopus was little-studied by western scientists before the 20th century. It was given a spectral class of F in 1897, an early use of this extension to Secchi class I, applied to those stars where the hydrogen lines are relatively weak and the calcium K line relatively strong. It was given as a standard star of F0 in the
Henry Draper Catalogue The ''Henry Draper Catalogue'' (HD) is an astronomical star catalogue published between 1918 and 1924, giving spectroscopic classifications for 225,300 stars; it was later expanded by the ''Henry Draper Extension'' (HDE), published between 192 ...
, with the spectral type F0 described as having hydrogen lines half the strength of an A0 star and the calcium K line three times as strong as Hδ. American astronomer Jesse Greenstein was interested in stellar spectra and used the newly built Otto Struve Telescope at McDonald Observatory to analyze the star's spectrum in detail. In a 1942 paper, he reported that the spectrum is dominated by strong broad hydrogen lines. There are also
absorption line Absorption spectroscopy is spectroscopy that involves techniques that measure the absorption (electromagnetic radiation), absorption of electromagnetic radiation, as a function of frequency or wavelength, due to its interaction with a sample. Th ...
s of carbon, nitrogen, oxygen, sulphur, iron, and many ionised metals. It was studied in the
ultraviolet Ultraviolet radiation, also known as simply UV, is electromagnetic radiation of wavelengths of 10–400 nanometers, shorter than that of visible light, but longer than X-rays. UV radiation is present in sunlight and constitutes about 10% of ...
by an early astronomical satellite, Gemini XI in 1966. The UV spectra were considered to be consistent with an F0
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 ...
having a temperature of , the accepted parameters for Canopus at the time. New Zealand-based astronomers John Hearnshaw and Krishna Desikachary examined the spectrum in greater detail, publishing their results in 1982. When
luminosity class In astronomy, stellar classification is the classification of stars based on their stellar spectrum, spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a Prism (optics), prism or diffraction gratin ...
es were added to the MK spectral classification scheme, Canopus was assigned class Iab indicating an intermediate luminosity supergiant. This was based on the relative strengths of certain spectral lines understood to be sensitive to the luminosity of a star. In the
Bright Star Catalogue The Bright Star Catalogue, also known as the Yale Catalogue of Bright Stars, Yale Bright Star Catalogue, or just YBS, is a star catalogue that lists all stars of stellar magnitude 6.5 or brighter, which is roughly every star visible to the na ...
5th edition it is given the spectral class F0II, the luminosity class indicating a
bright giant A giant star has a substantially larger radius and luminosity than a main-sequence (or ''dwarf'') star of the same surface temperature. They lie above the main sequence (luminosity class V in the Yerkes spectral classification) on the Hertzspr ...
. Balmer line profiles and oxygen line strengths indicate the size and luminosity of Canopus. When the effects of stellar rotation speed on spectral lines are accounted for, the MK spectral class of Canopus is adjusted to A9II. Its spectrum consists mostly of absorption lines on a visible continuum, but some emission has been detected. For example, the calcium K line has weak emission wings on each side of the strong central absorption line, first observed in 1966. The emission line profiles are usually correlated with the luminosity of the star as described by the Wilson-Bappu effect, but in the case of Canopus they indicate a luminosity much lower than that calculated by other methods. More detailed observations have shown that the emission line profiles are variable and may be due to plage areas on the surface of the star. Emission can also be found in other lines such as the h and k lines of ionised magnesium.


Distance

Before the launch of the
Hipparcos ''Hipparcos'' was a scientific satellite of the European Space Agency (ESA), launched in 1989 and operated until 1993. It was the first space experiment devoted to precision astrometry, the accurate measurement of the positions and distances of ...
satellite telescope, distance estimates for Canopus varied widely, from 96
light-year A light-year, alternatively spelled light year (ly or lyr), is a unit of length used to express astronomical distances and is equal to exactly , which is approximately 9.46 trillion km or 5.88 trillion mi. As defined by the International Astr ...
s to 1200 light-years (or 30 to 370 parsecs). For example, an old distance estimate of 200 parsecs (652 light years) gave it a luminosity of , far higher than modern estimates. The closer distance was derived from parallax measurements of around . The larger distance derives from the assumption of a very bright absolute magnitude for Canopus. Hipparcos established Canopus as being () from the
Solar System The Solar SystemCapitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Sola ...
; this is based on its 2007
parallax Parallax is a displacement or difference in the apparent position of an object viewed along two different sightline, lines of sight and is measured by the angle or half-angle of inclination between those two lines. Due to perspective (graphica ...
measurement of . At 95 parsecs, the interstellar extinction for Canopus is low at 0.26 magnitudes. Canopus is too bright to be included in the normal observation runs of the Gaia satellite and there is no published Gaia parallax for it. At present the star is drifting further away from the Sun with a
radial velocity The radial velocity or line-of-sight velocity of a target with respect to an observer is the rate of change of the vector displacement between the two points. It is formulated as the vector projection of the target-observer relative velocity ...
of 20 km/s. Some 3.1 million years ago it made the closest approach to the Sun at a distance of about . Canopus is orbiting the Milky Way with a heliocentric velocity of 24.5 km/s and a low
eccentricity Eccentricity or eccentric may refer to: * Eccentricity (behavior), odd behavior on the part of a person, as opposed to being "normal" Mathematics, science and technology Mathematics * Off-Centre (geometry), center, in geometry * Eccentricity (g ...
of 0.065.


Physical characteristics

The
absorption line Absorption spectroscopy is spectroscopy that involves techniques that measure the absorption (electromagnetic radiation), absorption of electromagnetic radiation, as a function of frequency or wavelength, due to its interaction with a sample. Th ...
s in the spectrum of Canopus shift slightly with a period of . This was first detected in 1906 and the Doppler variations were interpreted as orbital motion. An orbit was even calculated, but no such companion exists and the small radial velocity changes are due to movements in the atmosphere of the star. The maximum observed radial velocities are only 0.7 to . Canopus also has a magnetic field that varies with the same period, detected by the
Zeeman splitting The Zeeman effect () is the splitting of a spectral line into several components in the presence of a static magnetic field. It is caused by the interaction of the magnetic field with the magnetic moment of the atomic electron associated with ...
of its spectral lines. Canopus is bright at
microwave Microwave is a form of electromagnetic radiation with wavelengths shorter than other radio waves but longer than infrared waves. Its wavelength ranges from about one meter to one millimeter, corresponding to frequency, frequencies between 300&n ...
wavelengths, one of the few F-class stars to be detected by radio. The
rotation period In astronomy, the rotation period or spin period of a celestial object (e.g., star, planet, moon, asteroid) has two definitions. The first one corresponds to the '' sidereal rotation period'' (or ''sidereal day''), i.e., the time that the objec ...
of the star is not accurately known, but may be over three hundred days. The
projected rotational velocity Stellar rotation is the angular motion of a star about its axis. The rate of rotation can be measured from the spectrum of the star, or by timing the movements of active features on the surface. The rotation of a star produces an equatorial bu ...
has been measured at 9 km/s. An early
interferometric Interferometry is a technique which uses the '' interference'' of superimposed waves to extract information. Interferometry typically uses electromagnetic waves and is an important investigative technique in the fields of astronomy, fiber opt ...
measurement of its
angular diameter The angular diameter, angular size, apparent diameter, or apparent size is an angular separation (in units of angle) describing how large a sphere or circle appears from a given point of view. In the vision sciences, it is called the ''visual an ...
in 1968 gave a limb-darkened value of , close to the accepted modern value.
Very-long-baseline interferometry Very-long-baseline interferometry (VLBI) is a type of astronomical interferometry used in radio astronomy. In VLBI a signal from an astronomical radio source, such as a quasar, is collected at multiple radio telescopes on Earth or in space. T ...
has been used to calculate Canopus' angular diameter at . Combined with distance calculated from its Hipparcos parallax, this gives it a radius of 71 times that of the Sun. If it were at the centre of the Solar System, it would extend 90% of the way to the orbit of Mercury. The radius and temperature relative to the Sun means that it is 10,700 times more luminous than the Sun, and its position in the H-R diagram relative to theoretical
evolutionary Evolution is the change in the heritable characteristics of biological populations over successive generations. It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, resulting in certa ...
tracks means that it is times as massive as the Sun. Measurements of its shape find a 1.1° departure from spherical symmetry. Canopus is a source of
X-rays An X-ray (also known in many languages as Röntgen radiation) is a form of high-energy electromagnetic radiation with a wavelength shorter than those of ultraviolet rays and longer than those of gamma rays. Roughly, X-rays have a wavelength ran ...
, which are probably produced by its corona, magnetically heated to several million
Kelvin The kelvin (symbol: K) is the base unit for temperature in the International System of Units (SI). The Kelvin scale is an absolute temperature scale that starts at the lowest possible temperature (absolute zero), taken to be 0 K. By de ...
. The temperature has likely been stimulated by fast rotation combined with strong convection percolating through the star's outer layers. The soft X-ray sub-coronal X-ray emission is much weaker than the hard X-ray coronal emission. The same behaviour has been measured in other F-class supergiants such as
α Persei Alpha Persei ( Latinized from α Persei, abbreviated Alpha Per, α Per), formally named Mirfak (pronounced or ), is the brightest star in the northern constellation of Perseus, outshining the constellation's best-known st ...
and is now believed to be a normal property of such stars.


Evolution

The spectrum of Canopus indicates that it spent some 30 million years of its existence as a blue-white main sequence star of around 10 solar masses, before exhausting its core hydrogen and evolving away from the
main sequence In astronomy, the main sequence is a classification of stars which appear on plots of stellar color index, color versus absolute magnitude, brightness as a continuous and distinctive band. Stars on this band are known as main-sequence stars or d ...
. The position of Canopus in the H–R diagram indicates that it is currently in the core-helium burning phase. It is an intermediate mass star that has left the red-giant branch before its core became degenerate and is now in a
blue loop In the field of stellar evolution, a blue loop is a stage in the life of an evolved star where it changes from a cool star to a hotter one before cooling again. The name derives from the shape of the evolutionary track on a Hertzsprung–Russel ...
. Models of stellar evolution in the blue loop phase show that the length of the blue loop is strongly affected by rotation and mixing effects inside the star. It is difficult to determine whether a star is currently evolving towards hotter temperature or returning to cooler temperatures, since the evolutionary tracks for stars with different masses overlap during the blue loops. Canopus lies on the warm side of the instability strip and does not pulsate like Cepheid variables of a similar luminosity. However its atmosphere does appear to be unstable, showing strong signs of convection. Canopus may be massive enough to explode by an iron-core collapse supernova.


Cultural significance

Canopus was known to the ancient Mesopotamians and represented the city of Eridu in the ''Three Stars Each''
Babylonian star catalogues Babylonian astronomy collated earlier observations and divinations into sets of Babylonian star catalogues, during and after the Kassite rule over Babylonia. These star catalogues, written in cuneiform script, contained lists of constellations, ...
and later MUL.APIN around 1100 BC. Canopus was called MUL.NUNKI by the Babylonians, which translates as "star of the city of Eridu". Eridu was the southernmost and one of the oldest Sumerian cities. From there is a good view to the south, so that about 6000 years ago due to the precession of the Earth's axis the first rising of the star Canopus in Mesopotamia could be observed only from there at the southern meridian at midnight. Today, the star Sigma Sagittarii is known by the common name Nunki. Canopus was not visible to the mainland
ancient Greeks Ancient Greece () was a northeastern Mediterranean civilization, existing from the Greek Dark Ages of the 12th–9th centuries BC to the end of classical antiquity (), that comprised a loose collection of culturally and linguistically re ...
and Romans; it was, however, visible to the
ancient Egypt Ancient Egypt () was a cradle of civilization concentrated along the lower reaches of the Nile River in Northeast Africa. It emerged from prehistoric Egypt around 3150BC (according to conventional Egyptian chronology), when Upper and Lower E ...
ians.Schaaf, p. 107. Hence
Aratus Aratus (; ; c. 315/310 240 BC) was a Greek didactic poet. His major extant work is his hexameter poem ''Phenomena'' (, ''Phainómena'', "Appearances"; ), the first half of which is a verse setting of a lost work of the same name by Eudoxus of Cn ...
did not write of the star as it remained below the horizon, while
Eratosthenes Eratosthenes of Cyrene (; ;  – ) was an Ancient Greek polymath: a Greek mathematics, mathematician, geographer, poet, astronomer, and music theory, music theorist. He was a man of learning, becoming the chief librarian at the Library of A ...
and
Ptolemy Claudius Ptolemy (; , ; ; – 160s/170s AD) was a Greco-Roman mathematician, astronomer, astrologer, geographer, and music theorist who wrote about a dozen scientific treatises, three of which were important to later Byzantine science, Byzant ...
—observing from
Alexandria Alexandria ( ; ) is the List of cities and towns in Egypt#Largest cities, second largest city in Egypt and the List of coastal settlements of the Mediterranean Sea, largest city on the Mediterranean coast. It lies at the western edge of the Nile ...
—did, calling it ''Kanōbos''. An
Egypt Egypt ( , ), officially the Arab Republic of Egypt, is a country spanning the Northeast Africa, northeast corner of Africa and Western Asia, southwest corner of Asia via the Sinai Peninsula. It is bordered by the Mediterranean Sea to northe ...
ian priestly poet in the time of
Thutmose III Thutmose III (variously also spelt Tuthmosis or Thothmes), sometimes called Thutmose the Great, (1479–1425 BC) was the fifth pharaoh of the 18th Dynasty of Egypt. He is regarded as one of the greatest warriors, military commanders, and milita ...
mentions the star as ''Karbana,'' "the star which pours his light in a glance of fire, when he disperses the morning dew." Under the Ptolemies, the star was known as ''Ptolemaion'' (
Greek Greek may refer to: Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group *Greek language, a branch of the Indo-European language family **Proto-Greek language, the assumed last common ancestor of all kno ...
: Πτολεμαῖον) and its acronychal rising marked the date of the Ptolemaia festival, which was held every four years, from 262 to 145 BC. The Greek astronomer
Posidonius Posidonius (; , "of Poseidon") "of Apameia" (ὁ Ἀπαμεύς) or "of Rhodes" (ὁ Ῥόδιος) (), was a Greeks, Greek politician, astronomer, astrologer, geographer, historian, mathematician, and teacher native to Apamea (Syria), Apame ...
used observations of Canopus to calculate quite accurately the Earth's circumference, around 90 – 120 BC.


India

In Indian
Vedic literature FIle:Atharva-Veda samhita page 471 illustration.png, upright=1.2, The Vedas are ancient Sanskrit texts of Hinduism. Above: A page from the ''Atharvaveda''. The Vedas ( or ; ), sometimes collectively called the Veda, are a large body of relig ...
, Canopus is associated with the sage
Agastya Agastya was a revered Indian sage of Hinduism. In the Indian tradition, he is a noted recluse and an influential scholar in diverse languages of the Indian subcontinent. He is regarded in some traditions to be a Chiranjivi. He and his wife ...
, one of the ancient
siddhar The Siddhar (Tamil language, Tamil (romanized) ''cittar)'' in Tamils, Tamil tradition is a perfected individual who has attained spiritual powers called ''siddhi''. Historically, Siddhar also refers to the people who were early-age wandering ...
s and
rishi In Indian religions, a ''rishi'' ( ) is an accomplished and enlightened person. They find mention in various Vedic texts. Rishis are believed to have composed hymns of the Vedas. The Post-Vedic tradition of Hinduism regards the rishis as "gre ...
s (the others are associated with the stars of the
Big Dipper The Big Dipper (American English, US, Canadian English, Canada) or the Plough (British English, UK, Hiberno-English, Ireland) is an asterism (astronomy), asterism consisting of seven bright stars of the constellation Ursa Major; six of them ar ...
). To Agastya, the star is said to be the 'cleanser of waters', and its rising coincides with the calming of the waters of the
Indian Ocean The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or approximately 20% of the water area of Earth#Surface, Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia (continent), ...
. Canopus is described by
Pliny the Elder Gaius Plinius Secundus (AD 23/24 79), known in English as Pliny the Elder ( ), was a Roman Empire, Roman author, Natural history, naturalist, and naval and army commander of the early Roman Empire, and a friend of the Roman emperor, emperor Vesp ...
and
Gaius Julius Solinus __NOTOC__ Gaius Julius Solinus, better known simply as Solinus, was a Latin grammarian, geographer, and compiler who probably flourished in the early 3rd century AD. Historical scholar Theodor Mommsen dates him to the middle of the 3rd century. ...
as the largest, brightest and only source of
starlight Starlight is the light emitted by stars. It typically refers to visible electromagnetic radiation from stars other than the Sun, observable from Earth at night, although a component of starlight is observable from Earth during daytime. Sunlig ...
for navigators near Tamraparni island (ancient Sri Lanka) during many nights.


Iran (Persia)

Canopus, known as Suhail (سُهَيْل) in
Arabic Arabic (, , or , ) is a Central Semitic languages, Central Semitic language of the Afroasiatic languages, Afroasiatic language family spoken primarily in the Arab world. The International Organization for Standardization (ISO) assigns lang ...
and Soheil (سهیل) in
Farsi Persian ( ), also known by its endonym Farsi (, Fārsī ), is a Western Iranian language belonging to the Iranian branch of the Indo-Iranian subdivision of the Indo-European languages. Persian is a pluricentric language predominantly spoke ...
, holds significant cultural importance in Iran. Its visibility in
Iran Iran, officially the Islamic Republic of Iran (IRI) and also known as Persia, is a country in West Asia. It borders Iraq to the west, Turkey, Azerbaijan, and Armenia to the northwest, the Caspian Sea to the north, Turkmenistan to the nort ...
varies due to the country's range of latitudes. For instance, in the
Alborz Mountains The Alborz ( ) range, also spelled as Alburz, Elburz or Elborz, is a mountain range in northern Iran that stretches from the border of Azerbaijan along the western and entire southern coast of the Caspian Sea and finally runs northeast and merge ...
, at approximately 36°N latitude, Canopus rises just one degree above the southern horizon, making it a rare sight. This rarity has led to the Persian expression "ستاره سهیل شدن" ("becoming the star Soheil"), used to describe someone who is seldom seen or elusive. The term "Soheil" symbolizes rarity in
Persian literature Persian literature comprises oral compositions and written texts in the Persian language and is one of the world's oldest literatures. It spans over two-and-a-half millennia. Its sources have been within Greater Iran including present-day ...
, reflecting the star's infrequent visibility in the region.
Ferdowsi Abu'l-Qâsem Ferdowsi Tusi (also Firdawsi, ; 940 – 1019/1025) was a Persians, Persian poet and the author of ''Shahnameh'' ("Book of Kings"), which is one of the world's longest epic poetry, epic poems created by a single poet, and the gre ...
references Canopus in his poetry, associating it with
Yemen Yemen, officially the Republic of Yemen, is a country in West Asia. Located in South Arabia, southern Arabia, it borders Saudi Arabia to Saudi Arabia–Yemen border, the north, Oman to Oman–Yemen border, the northeast, the south-eastern part ...
: ز سر تا بپایش گلست و سمن به سرو سهی بر سهیل یمن Ze sar tā be-pāyash golast o saman Be sarv-e sehī bar Sohayl-e Yaman From head to toe, she is adorned with flowers and jasmine, Like the tall cypress under the Canopus of Yemen. Ferdowsi uses Canopus as a metaphor for beauty and rarity, linking it to Yemen, where the star is visible. The star's name also appears in Persian literary works, such as Anvār-i Suhaylī (انوار سهیلی) ("Lights of Canopus"), a 15th-century Persian adaptation of
Kalīla wa-Dimna ''Kalīla wa-Dimna'' or ''Kelileh o Demneh'' () is a collection of fables. The book consists of fifteen chapters containing many fables whose heroes are animals. A remarkable animal character is the lion, who plays the role of the king; he has ...
(کلیله و دمنه) (itself an earlier Persian translation of the ancient Indian
Panchatantra The ''Panchatantra'' ( IAST: Pañcatantra, ISO: Pañcatantra, , "Five Treatises") is an ancient Indian collection of interrelated animal fables in Sanskrit verse and prose, arranged within a frame story.
).These works highlight the cultural significance of Canopus in Persian literature.


China

Canopus was described as Shou Xing, the Star of Longevity, in the ''Shiji'' (
Records of the Grand Historian The ''Shiji'', also known as ''Records of the Grand Historian'' or ''The Grand Scribe's Records'', is a Chinese historical text that is the first of the Twenty-Four Histories of imperial China. It was written during the late 2nd and early 1st ce ...
) completed in 94 BC by Chinese historian
Sima Qian Sima Qian () was a Chinese historian during the early Han dynasty. He is considered the father of Chinese historiography for the ''Shiji'' (sometimes translated into English as ''Records of the Grand Historian''), a general history of China cov ...
. Drawing on sources from the
Warring States period The Warring States period in history of China, Chinese history (221 BC) comprises the final two and a half centuries of the Zhou dynasty (256 BC), which were characterized by frequent warfare, bureaucratic and military reforms, and ...
, he noted it to be the southern counterpart of
Sirius Sirius is the brightest star in the night sky. Its name is derived from the Greek word (Latin script: ), meaning 'glowing' or 'scorching'. The star is designated  Canis Majoris, Latinized to Alpha Canis Majoris, and abbr ...
, and wrote of a sanctuary dedicated to it established by Emperor
Qin Shi Huang Qin Shi Huang (, ; February 25912 July 210 BC), born Ying Zheng () or Zhao Zheng (), was the founder of the Qin dynasty and the first emperor of China. He is widely regarded as the first ever supreme leader of a unitary state, unitary d ...
between 221 and 210 BC. During the
Han dynasty The Han dynasty was an Dynasties of China, imperial dynasty of China (202 BC9 AD, 25–220 AD) established by Liu Bang and ruled by the House of Liu. The dynasty was preceded by the short-lived Qin dynasty (221–206 BC ...
, the star was auspicious, its appearance in the southern sky heralding peace and absence war. From the imperial capital
Chang'an Chang'an (; zh, t=長安, s=长安, p=Cháng'ān, first=t) is the traditional name of the city now named Xi'an and was the capital of several Chinese dynasties, ranging from 202 BCE to 907 CE. The site has been inhabited since Neolithic time ...
, the star made a low transit across the southern sky, indicating true south to observers, and was often obscured by clouds. During this time it was also equated with Old Man of the South Pole (in ) Under this name, Canopus appears (albeit misplaced northwards) on the medieval Chinese manuscript the Dunhuang Star Chart, although it cannot be seen from the Chinese capital of
Chang'an Chang'an (; zh, t=長安, s=长安, p=Cháng'ān, first=t) is the traditional name of the city now named Xi'an and was the capital of several Chinese dynasties, ranging from 202 BCE to 907 CE. The site has been inhabited since Neolithic time ...
. The Chinese astronomer
Yi Xing Yixing (, 683–727) was a Buddhist monk of the Tang dynasty, recognized for his accomplishments as an astronomer, a reformer of the calendar system, a specialist in the ''I Ching, Yijing'' (易經), and a distinguished Buddhist figure with exp ...
had journeyed south to chart Canopus and other far southern stars in 724 AD. Its personification as the Old Man Star was popularised in the
Tang dynasty The Tang dynasty (, ; zh, c=唐朝), or the Tang Empire, was an Dynasties of China, imperial dynasty of China that ruled from 618 to 907, with an Wu Zhou, interregnum between 690 and 705. It was preceded by the Sui dynasty and followed ...
, where it appeared often in poetry and memorials. Later still, during the
Ming dynasty The Ming dynasty, officially the Great Ming, was an Dynasties of China, imperial dynasty of China that ruled from 1368 to 1644, following the collapse of the Mongol Empire, Mongol-led Yuan dynasty. The Ming was the last imperial dynasty of ...
, the star was established as one of the Three Stars (Fu Lo Shou), appearing frequently in art and literature of the time. This symbolism spread into neighbouring cultures in Asia. In Japan, Canopus is known as ''Mera-boshi'' and ''Roujin-sei'' (the old man star), and in Mongolia, it was personified as the White Old Man. Although the link was known in Tibet, with names such as ''Genpo karpo'' (''Rgan po dkar po'') or ''Genkar'' (''Rgan dkar'') "White Old Man", the symbolism was not popular. Instead, Canopus was more commonly named ''Karma Rishi སྐར་མ་རི་ཥི།'', derived from Indian mythology. Tibetans celebrated the star's heliacal rising with ritual bathing and associated it with morning dew.


Polynesia

Bright stars were important to the ancient
Polynesians Polynesians are an ethnolinguistic group comprising closely related ethnic groups native to Polynesia, which encompasses the islands within the Polynesian Triangle in the Pacific Ocean. They trace their early prehistoric origins to Island Sout ...
for navigation between the many islands and atolls of the Pacific Ocean. Low on the horizon, they acted as stellar compasses to assist mariners in charting courses to particular destinations. Canopus served as the southern wingtip of a "Great Bird" constellation called ''Manu'', with Sirius as the body and
Procyon Procyon () is the brightest star in the constellation of Canis Minor and usually the list of brightest stars, eighth-brightest star in the night sky, with an apparent visual magnitude of 0.34. It has the Bayer designation α Canis Min ...
the northern wingtip, which divided the Polynesian night sky into two hemispheres. The Hawaiian people called Canopus ''Ke Alii-o-kona-i-ka-lewa'', "The chief of the southern expanse"; it was one of the stars used by Hawaiʻiloa and Ki when they traveled to the
Southern Ocean The Southern Ocean, also known as the Antarctic Ocean, comprises the southernmost waters of the world ocean, generally taken to be south of 60th parallel south, 60° S latitude and encircling Antarctica. With a size of , it is the seco ...
. The
Māori people Māori () are the Indigenous peoples of Oceania, indigenous Polynesians, Polynesian people of mainland New Zealand. Māori originated with settlers from East Polynesia, who arrived in New Zealand in several waves of Māori migration canoes, c ...
of New Zealand/Aotearoa had several names for Canopus. ''
Ariki An ariki (New Zealand, Cook Islands), ꞌariki ( Easter Island), aliki (Tokelau, Tuvalu), ali‘i (Samoa, Hawai‘i), ari'i (Society Islands, Tahiti), Rotuma) aiki or hakaiki ( Marquesas Islands), akariki (Gambier Islands) or ‘eiki (Tonga) is o ...
'' ("High-born"), was known as a solitary star that appeared in the east, prompting people to weep and chant. They also named it '' Atutahi'', ''Aotahi'' or ''Atuatahi'', "Stand Alone". Its solitary nature indicates it is a '' tapu'' star, as ''tapu'' people are often solitary. Its appearance at the beginning of the ''Maruaroa'' season foretells the coming winter; light rays to the south indicate a cold wet winter, and to the north foretell a mild winter. Food was offered to the star on its appearance. This name has several mythologies attached to it. One story tells of how Atutahi was left outside the basket representing 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 ...
when Tāne wove it. Another related myth about the star says that Atutahi was the first-born child of Rangi, who refused to enter the Milky Way and so turned it sideways and rose before it. The same name is used for other stars and constellations throughout Polynesia. ''Kapae-poto'', "Short horizon", referred to it rarely setting as seen in New Zealand; ''Kauanga'' ("Solitary") was the name for Canopus only when it was the last star visible before sunrise. The people of the
Society Islands The Society Islands ( , officially ; ) are an archipelago in the South Pacific Ocean that includes the major islands of Tahiti, Mo'orea, Moorea, Raiatea, Bora Bora and Huahine. Politically, they are part of French Polynesia, an overseas country ...
had two names for Canopus, as did the
Tuamotu The Tuamotu Archipelago or the Tuamotu Islands (, officially ) are a French Polynesian chain of just under 80 islands and atolls in the southern Pacific Ocean. They constitute the largest chain of atolls in the world, extending (from northwest to ...
people. The Society Islanders called Canopus ''Taurua-e-tupu-tai-nanu'', "Festivity-whence-comes-the-flux-of-the-sea", and ''Taurua-nui-o-te-hiti-apatoa'' "Great-festivity-of-the-border-of-the-south", and the Tuamotu people called the star ''Te Tau-rari'' and ''Marere-te-tavahi'', the latter said to be the true name for the former, "He-who-stands-alone".


Africa

In the
Guanche Guanche may refer to: *Guanches, the indigenous people of the Canary Islands *Guanche language, an extinct language, spoken by the Guanches until the 16th or 17th century *''Conus guanche ''Conus guanche'' is a species of sea snail, a marine ga ...
mythology of the island of
Tenerife Tenerife ( ; ; formerly spelled ''Teneriffe'') is the largest and most populous island of the Canary Islands, an Autonomous communities of Spain, autonomous community of Spain. With a land area of and a population of 965,575 inhabitants as of A ...
(Spain), the star Canopus was linked with the goddess Chaxiraxi. The
Tswana people The Batswana (, singular ''Motswana'') are a Bantu peoples, Bantu Ethnic groups in South Africa, ethnic group native to Southern Africa that are descendants of King Looe (Lowe) who established the Hurutshi tribe in Southern Africa (linguistic ...
of
Botswana Botswana, officially the Republic of Botswana, is a landlocked country in Southern Africa. Botswana is topographically flat, with approximately 70 percent of its territory part of the Kalahari Desert. It is bordered by South Africa to the sou ...
knew Canopus as ''Naka''. Appearing late in winter skies, it heralded increasing winds and a time when trees lose their leaves. Stock owners knew it was time to put their sheep with rams. In southern Africa, the Sotho, Tswana and Venda people called Canopus ''Naka'' or ''Nanga'', “the Horn Star”, while the Zulu and Swazi called it ''inKhwenkwezi'' "Brilliant star". It appears in the predawn sky in the third week of May. According to the Venda, the first person to see Canopus would blow a ''phalaphala'' horn from the top of a hill, getting a cow for a reward. The Sotho chiefs also awarded a cow, and ordered their medicine men to roll bone dice and read the fortune for the coming year. To the ǀXam-speaking
Bushmen The San peoples (also Saan), or Bushmen, are the members of any of the indigenous hunter-gatherer cultures of southern Africa, and the Indigenous peoples of Africa, oldest surviving cultures of the region. They are thought to have diverged fro ...
of South Africa, Canopus and Sirius signalled the appearance of termites and flying ants. They also believed that stars had the power to cause death and misfortune, and they would pray to
Sirius Sirius is the brightest star in the night sky. Its name is derived from the Greek word (Latin script: ), meaning 'glowing' or 'scorching'. The star is designated  Canis Majoris, Latinized to Alpha Canis Majoris, and abbr ...
and Canopus in particular to impart good fortune or skill. The
ǃKung people The ǃKung ( ) are one of the San peoples who live mostly on the western edge of the Kalahari Desert, Kalahari desert, Ovamboland (northern Namibia and southern Angola), and Botswana. The names ''ǃKung'' (''ǃXun'') and ''Ju'' are variant w ...
of the
Kalahari Desert The Kalahari Desert is a large semiarid climate, semiarid sandy savanna in Southern Africa covering including much of Botswana as well as parts of Namibia and South Africa. It is not to be confused with the Angolan, Namibian, and South African ...
in Botswana held Canopus and Capella to be the horns of ''tshxum'' (the Pleiades), the appearance of all three marking the end of the dry season and start of the rainy season.


Americas

The
Navajo The Navajo or Diné are an Indigenous people of the Southwestern United States. Their traditional language is Diné bizaad, a Southern Athabascan language. The states with the largest Diné populations are Arizona (140,263) and New Mexico (1 ...
observed the star and named it ''Maʼii Bizòʼ'', the “Coyote Star”. According to legend, Maʼii (Coyote) took part in the naming and placing of the star constellations during the creation of the universe. He placed Canopus directly south, naming it after himself.Maryboy, Nancy D. (2004). ''A Guide to Navajo Astronomy.'' Indigenous Education Institute : Bluff, Utah. The Kalapalo people of
Mato Grosso Mato Grosso ( – ) is one of the states of Brazil, the List of Brazilian states by area, third largest by area, located in the Central-West Region, Brazil, Central-West region. The state has 1.66% of the Brazilian population and is responsible ...
state in Brazil saw Canopus and
Procyon Procyon () is the brightest star in the constellation of Canis Minor and usually the list of brightest stars, eighth-brightest star in the night sky, with an apparent visual magnitude of 0.34. It has the Bayer designation α Canis Min ...
as ''Kofongo'' "Duck", with Castor and Pollux representing his hands. The asterism's appearance signified the coming of the rainy season and increase in
manioc ''Manihot esculenta'', common name, commonly called cassava, manioc, or yuca (among numerous regional names), is a woody shrub of the spurge family, Euphorbiaceae, native to South America, from Brazil, Paraguay and parts of the Andes. Although ...
, a food staple fed to guests at feasts.


Australia

Canopus is identified as the moiety ancestor ''Waa'' "Crow" to some Koori people in southeastern Australia. The Boorong people of northwestern Victoria recalled that ''War'' (Canopus) was the brother of ''Warepil'' (Sirius), and that he brought fire from the heavens and introduced it to humanity. His wife was ''Collowgullouric War'' ( Eta Carinae). The Pirt-Kopan-noot people of western Victoria tell of ''Waa'' "Crow" falling in love with a queen, ''Gneeanggar'' "Wedge-tailed Eagle" (Sirius) and her six attendants (the Pleiades). His advances spurned, he hears that the women are foraging for grubs and so transforms himself into a grub. When the women dig him out, he changes into a giant and carries her off. The Kulin people know Canopus as ''Lo-an-tuka''. Objects in the sky are also associated with states of being for some tribes; the Wailwun of northern New South Wales know Canopus as ''Wumba'' "deaf", alongside Mars as ''Gumba'' "fat" and Venus as ''Ngindigindoer'' "you are laughing". Tasmanian aboriginal lore holds that Canopus is ''Dromerdene'', the brother of ''Moinee''; the two fought and fell out of the sky, with ''Dromerdene'' falling into Louisa Bay in southwest Tasmania. Astronomer Duane Hamacher has identified Canopus with ''Moinee'' in a paper dating Tasmanian Aboriginal oral tradition to the late Pleistocene, when Canopus was much closer to the South
celestial pole The north and south celestial poles are the two points in the sky where Earth's axis of rotation, indefinitely extended, intersects the celestial sphere. The north and south celestial poles appear permanently directly overhead to observers at ...
.


Legacy

Canopus appears on the
flag of Brazil The national flag of Brazil is a blue disc depicting a starry sky (which includes the Crux, Southern Cross) spanned by a curved band inscribed with the List of national mottos, national motto ('Order and Progress'), within a yellow rhombus, on ...
, symbolising the state of
Goiás Goiás () is a Brazilian States of Brazil, state located in the Central-West Region, Brazil, Central-West region. Goiás borders the Federal District (Brazil), Federal District and the states of (from north clockwise) Tocantins, Bahia, Minas Ge ...
. Two U.S. Navy
submarine tender A submarine tender, in British English a submarine depot ship, is a type of depot ship that supplies and supports submarines. Development Submarines are small compared to most oceangoing vessels, and generally cannot carry large amounts of foo ...
s have been named after Canopus, the first serving from 1922 to 1942 and the
second The second (symbol: s) is a unit of time derived from the division of the day first into 24 hours, then to 60 minutes, and finally to 60 seconds each (24 × 60 × 60 = 86400). The current and formal definition in the International System of U ...
serving from 1965 to 1994. The
Royal Navy The Royal Navy (RN) is the naval warfare force of the United Kingdom. It is a component of His Majesty's Naval Service, and its officers hold their commissions from the King of the United Kingdom, King. Although warships were used by Kingdom ...
built nine Canopus-class ships of the line in the early 19th century, and six s which entered services between 1899 and 1902. There are at least two mountains named after the star: Mount Canopus in Antarctica; and Mount Canopus or Canopus Hill in
Tasmania Tasmania (; palawa kani: ''Lutruwita'') is an island States and territories of Australia, state of Australia. It is located to the south of the Mainland Australia, Australian mainland, and is separated from it by the Bass Strait. The sta ...
, the location of the Canopus Hill astronomical observatory.


In popular culture

* The fictional planet Arrakis, of
Frank Herbert Franklin Patrick Herbert Jr. (October 8, 1920February 11, 1986) was an American science-fiction author, best known for his 1965 novel Dune (novel), ''Dune'' and its five sequels. He also wrote short stories and worked as a newspaper journalist, ...
's 1965 novel ''
Dune A dune is a landform composed of wind- or water-driven sand. It typically takes the form of a mound, ridge, or hill. An area with dunes is called a dune system or a dune complex. A large dune complex is called a dune field, while broad, flat ...
,'' orbits Canopus. * Canopus is the home of superior and benevolent aliens in Doris Lessing's '' Canopus in Argos'' books."Doris Lessing on Feminism, Communism and 'Space Fiction'"
/ref> * Canopus is a system present in the video game Helldivers 2, host to a desert world.


See also

*
List of brightest stars This is a list of stars arranged by their apparent magnitude – their brightness as observed from Earth. It includes all stars brighter than magnitude +2.50 in visible light, measured using a ''V''-band filter in the UBV photometric system. St ...
*
List of most luminous stars This is a list of stars arranged by their absolute magnitude – their intrinsic stellar luminosity. This cannot be observed directly, so instead must be calculated from the apparent magnitude (the brightness as seen from Earth), the distanc ...
* List of nearest supergiants


References


Bibliography

* * {{DEFAULTSORT:Canopus Carinae, Alpha Carina (constellation) A-type bright giants 045348 030438 2326 Durchmusterung objects
Canopus Canopus is the brightest star in the southern constellation of Carina (constellation), Carina and the list of brightest stars, second-brightest star in the night sky. It is also Bayer designation, designated α Carinae, which is Rom ...