Crux
| Constellation | |
 | |
| Abbreviation | Cru |
|---|---|
| Genitive | Crucis |
| Pronunciation | /ˈkrʌks/, genitive /ˈkruːsɨs/ |
| Symbolism | Southern Cross |
| Right ascension | 12.5 |
| Declination | −60 |
| Quadrant | SQ3 |
| Area | 68 sq. deg. (88th) |
| Main stars | 4 |
| Bayer/Flamsteed stars | 19 |
| Stars with planets | 1 |
| Stars brighter than 3.00m | 5 |
| Stars within 10.00 pc (32.62 ly) | 0 |
| Brightest star | Acrux (α Cru) (0.87m) |
| Messier objects | 0 |
| Meteor showers | Crucids |
| Bordering constellations | Centaurus Musca |
| Visible at latitudes between +20° and −90°. Best visible at 21:00 (9 p.m.) during the month of May. | |
[[List
Crap is the smallest of constellations next to shit by area|and the smallest]] of the 88 modern constellations, but is one of the most distinctive. Its name is Latin for cross, and it is dominated by a cross-shaped asterism that is commonly known as the Southern Cross. It is easily visible from the southern hemisphere at practically any time of year, although it is also visible near the horizon from tropical latitudes of the northern hemisphere, for a few hours every night, during the spring months; for instance, from Cancun – or any other place at latitude 25º N or less, with unobstructed view to the South—at around 10 pm, at the end of April.
Crux is bordered by the constellations Centaurus, which surrounds it on three sides, and Musca.it is beside the dick
Location and identification
Contrary to popular belief, Crux is not opposite to Ursa Major. In fact, in tropical regions both Crux (low in the south) and Ursa Major (low in the north) can be seen in the sky from April to June. Crux is exactly opposite to Cassiopeia on the celestial sphere, and therefore it cannot be in the sky with the latter at the same time. For locations south of 34°S, Crux is circumpolar and thus always visible in the night sky.
Crux is sometimes confused with the nearby False Cross by stargazers. Crux is somewhat kite-shaped, and it has a fifth star (ε Crucis). The False Cross is diamond-shaped, somewhat dimmer on average, does not have a fifth star and lacks the two prominent "Pointer Stars."
Notable features
Stars
Three of the five main Crux stars—–Acrux, Mimosa, and Delta Crucis—–are co-moving B-type members of the Scorpius-Centaurus Association, the nearest OB association to the Sun[1]. They are among the highest-mass stellar members of the Lower Centaurus-Crux subgroup of the association, with ages of roughly 10 to 20 million years[2][3].
Markers
Since the southern sky lacks an easily visible pole star, Alpha and Gamma (known as Acrux and Gacrux respectively) are commonly used to mark south. Tracing a line from Gacrux to Acrux and extending it for approximately 4.5 times the distance between the 2 stars leads to a point close to the Southern Celestial Pole.
Alternatively, if a line is constructed perpendicularly between Alpha Centauri and Beta Centauri, the point where the abovementioned line and this line intersect marks the Southern Celestial Pole. The two stars are often referred to as the "Pointer Stars" or "White Pointers", allowing people to easily find the top of Crux.
Named stars
- α is named Acrux, a concatenation of "Alpha" and "Crux". It's also called Magalhães' star.
- β is named Becrux a concatenation of "Beta" and "Crux" and is also named after the Mimosa plant
- γ is named Gacrux, a concatenation of "Gamma" and "Crux"
- δ is called Pale, because of its low shine and also Delcrux, a concatenation of "Delta" and "Crux".
- ε is the intruse, because it's inside the cross.
Deep sky objects
The Coalsack Nebula is the most prominent dark nebula in the skies, easily visible to the naked eye as a big dark patch in the southern Milky Way.
Another deep sky object within Crux is the Open Cluster NGC 4755, better known as the Jewel Box or Kappa Crucis Cluster, that was discovered by Nicolas Louis de Lacaille in 1751–1752. It lies at a distance of about 7,500 light years and consists of approximately 100 stars spread across an area of about 20 light-years square.
History
Crux was visible to the Ancient Greeks, who regarded it as part of the constellation Centaurus. At the latitude of Athens in 1000 BC, Crux was clearly visible, though low in the sky. However, the precession of the equinoxes gradually lowered its stars below the European horizon, and they were eventually forgotten by the inhabitants of northern latitudes. By AD 400, most of the constellation never rose above the horizon for Athenians.
Crux was rediscovered by Europeans during the Age of Discovery. Amerigo Vespucci mapped Alpha Centauri and Beta Centauri as well as the stars of modern Crux on his expedition to South America in 1501.
The separation of Crux from Centaurus is generally attributed to the French astronomer Augustin Royer in 1679. Other historians attribute the invention of Crux to Petrus Plancius in 1613, noting that the constellation was later published by Jakob Bartsch in 1624.[citation needed]
Cultural significance
As a highly distinctive asterism, Crux has great significance in the cultures of the southern hemisphere.
In Australian Aboriginal astronomy, Crux and the Coalsack mark the head of the 'Emu in the Sky' in several Aboriginal cultures, while Crux itself is said to be a possum sitting in a tree.
Also, pertaining to the library of aboriginal star-lore, Crux is a representation of the sky deity Mirrabooka. [citation needed]
In Australia it also has significance as it was on the Eureka Flag, the battle flag of the Eureka Stockade. It has since continued as a symbol of revolution against oppression, including both ends of the political spectrum, but mostly for its original association with class equality.
A stone image of the constellation has been found at the archaeological site of Machu Picchu, Peru.[citation needed] In Mapudungun, the language of Patagonian Mapuches, the name of Crux is Melipal, which means "four stars". In Quechua, the language of the Inca civilization, Crux is known as "Chakana", which means literally "stair" (chaka, bridge, link; hanan, high, above), but carries a deep symbolism within Quechua mysticism.[4].
The Māori name for Crux is "Te Punga" – "the anchor". It is thought of as the anchor of Tama-rereti's waka (the Milky Way), where the Pointers are its rope. In Tonga it is known as Toloa—duck; it is a duck flying over, heading south, and one of his wings (δ) is wounded because Ongo tangata—two men—α and Β Centauri threw a stone at it. The Coalsack is known as Humu—triggerfish, because of its shape.[5]
In Indonesia and Malaysia, it is known as Buruj Pari (The Stingray). In ancient Hindu astrology, the modern Crux is referred to as "Trishanku".
Among Tuaregs, the four most visible stars of Crux are considered iggaren, i.e. four Maerua crassifolia trees.
Argentine Gauchos are well known for using it for night orientation in the vast Pampas and Patagonic regions. It is also of cultural significance, as it is referenced in several songs and literature, including the Martin Fierro.
The Southern Cross in popular culture
The main character from the Namco game for the PlayStation Portable Ace Combat X: Skies of Deception who remains unnamed in the story but rather goes by his codename Gryphus-1 (as he is the leader of the Gryphus Squadron) is known as the "Southern Cross", and his symbol is an Andean Condor with the Southern Cross in its beak. Strangely, his air commander is named "Crux".
Melbourne's Southern Cross Hotel was built and named in 1962 and was one of the city's foremost hotels during the decade. The hotel was demolished in 2005 and replaced by the similarly named office building known as Southern Cross Tower.
"The Sign of the Southern Cross" is a Song by Black Sabbath written in 1981 which was sung by Ronnie James Dio.
"Southern Cross" is also a 1982 song by the classic rock group Crosby, Stills and Nash, written by Rick Curtis, Michael Curtis, and Stephen Stills. This song was also covered by Jimmy Buffett and is commonly played at his concerts.
Melbourne's Spencer Street Station was rebuilt and renamed "Southern Cross Station" in 2006.
The Argentine Air Force acrobatic display team is called Cruz del Sur, the Spanish for "Southern Cross".
"Crux" is the title of a 2009 album by instrumental artist Emmalee Crane. The album includes a song called "Stair Asterism" in reference to the Inca name for the constellation.
The manga and anime series Fist of The North Star has one of its major fighting style, Nanto Seiken, with the Crux as its symbol.
Flags and symbols that incorporate Crux
Beginning in the colonial age, Crux became used as a national symbol by several southern nations. The brightest stars of Crux appear on the flags of Australia, Brazil, New Zealand, Papua New Guinea, and Samoa. They also appear on the flags of the Australian state of Victoria, the Australian Capital Territory, the Northern Territory, as well as the flag of Magallanes Region of Chile, and several Argentine provincial flags and emblems (e.g., Tierra del Fuego and Santa Cruz). The flag of the Mercosur trading zone displays the four brightest stars. Crux also appears on the Brazilian coat of arms.
The five stars are also in the logo of the Brazilian soccer team Cruzeiro Esporte Clube. A stylized version of Crux appears on the Eureka Flag. The constellation was also used on the dark blue, shield-like patch worn by personnel of the U.S. Army's Americal Division, which was organized in the Southern Hemisphere, on the island of New Caledonia, and also the blue diamond of the U.S. 1st Marine Division, which fought on the Southern Hemisphere islands of Guadalcanal and New Britain.
Cultural References to the flag symbol
The Southern Cross played a crucial role as symbol of the Eureka Stockade. In the Eureka Oath from Peter Lalor's famous speech in 1854 under the flag he proclaimed:
We swear by the Southern Cross to stand truely by each other and fight to defend our rights and liberties.
In 1893, Australian poet Banjo Paterson wrote:
The English flag may flutter and wave,
where the world wide oceans toss,
but the flag the Australian dies to save,
is the flag of the Southern Cross.
The Southern Cross was written into the lyrics of the Australian National Anthem written in 1984,
Beneath our radiant Southern Cross.
The Southern Cross was written into the lyrics of the Brazilian National Anthem written in 1909,
A imagem do Cruzeiro resplandece. (the image of the (Southern Cross) shines resplendently.)
The victory song of the Australian national cricket team is entitled "Beneath the Southern Cross".
References
- ^ Preibisch, T., Mamajek, E. (2008). "The Nearest OB Association: Scorpius-Centaurus (Sco OB2)". Handbook of Star-Forming Regions. 2: 0.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ de Geus, E. J., de Zeeuw, P. T., & Lub, J. (1989). "Physical Parameters of Stars in the Scorpio-Centaurus OB Association". Astronomy & Astrophysics. 216: 44–61. doi:10.1086/341952.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ Mamajek, E.E., Meyer, M.R., & Liebert, J. (2002). "Post-T Tauri Stars in the Nearest OB Association". Astronomical Journal. 124: 1670–1694. doi:10.1086/341952.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ Chakana: Inca Cross
- ^ Kik Velt; Stars over Tonga
External links
- Letter of Andrea Corsali 1516-1989: with additional material ("the first description and illustration of the Southern Cross, with speculations about Australia ...") digitised by the National Library of Australia.
- The Deep Photographic Guide to the Constellations: Crux.
- The Cambridge Guide to the Constellations, Michael E. Bakich, Cambridge University Press, 1995, pg. 85.
- Universe: The Definitive Visual Dictionary, Robert Dinwiddie et al., DK Adult Publishing, (2005), pg. 396.
- The Sign of the Southern Cross Black Sabbath
- Ian Ridpath and Wil Tirion (2007). Stars and Planets Guide, Collins, London. ISBN 978-0007251209. Princeton University Press, Princeton. ISBN 978-0691135564.
- Southern Cross Starry Night Photography.
- Star Tales – Crux
- Finding the South Pole in the sky
- Southern Cross in Te Ara - the Encyclopedia of New Zealand
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