* The Southern Cross *

Crux, being Latin for cross, commonly known as the Southern Cross (in contrast to the Northern Cross), is the smallest of the 88 modern constellations, but nevertheless one of the most distinctive. It is surrounded on three sides by the constellation Centaurus while to the south lies the Fly (Musca). Crux was originally thought of by ancient Greeks as part of Centaurus, but was defined as a separate asterism in the 16th century after Amerigo Vespucci's expedition to South America in 1501. Vespucci mapped the two stars, Alpha Centauri and Beta Centauri as well as the stars of the Crux. Although these stars were known to the ancient Greeks, gradual precession of the equinoxes had lowered them below the European skyline so that they were forgotten. For example at the latitude of Britain in 5000BC the constellation still was completely visible at springtime midnight.
Notable deep sky objects
The Coalsack Nebula is the most prominent dark nebula in the skies, well visible to the naked eye as 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.HistoryDue to precession of the equinox the stars comprising Crux were visible from the Mediterranean area in old times , so their stars had to be known by Greek astronomers. However, it was not regarded as a constellation of its own, but rather as part of Centaurus.The invention of Crux as a separate constellation is generally attributed to the French astronomer Augustin Royer in 1679. It was known in that shape well before that, however.The five brightest stars of Crux (a, ß, ?, d, and e Crucis) appear on the flags of Australia, Brazil, New Zealand ( the epsilon star is omitted), Papua New Guinea, and Samoa, and also the Australian States and Territories 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. The flag of the Mercosur trading zone displays the four brightest stars (epsilon omitted). Crux also appears on the Brazilian coat of arms. 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 Hemisplere, 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.A stone image of the constellation has also been left at the archaelogical site of Machu Picchu, Peru.Other names for Crux * In ancient Hindu astrology, the modern Crux is referred to as "trishanku". * The Maori name for Crux is "Te Punga" - "the anchor". It is thought of as 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 (d) is wounded because Ongo tangata — 2 men — a and ? Centauri threw a stone at it. The Coalsack is known as Humu — triggerfish, because of its shape.[2]
* Among Tuaregs, the 4 most visible stars of Crux are considered iggaren, i.e. four Maerua Crassifolia trees.
Stars
The Southern Cross is clearly visible above the aurora australis in this photograph taken from Dunedin, New Zealand.
The red giant Gacrux is clearly a different colour to the other three main stars, which are blue-white
Crux is clearly visible above the aurora australis in this photograph taken from Dunedin, New Zealand. The red giant Gacrux is clearly a different colour to the other three main stars, which are blue-white Stars with proper names:
* (a1,2 Cru) – 0.87 (double 1.3, 1.73) Acrux
* (ß Cru) 1.25 Becrux or Mimosa * (? Cru) – double 1.59, 6.42 Gacrux
* (d Cru) 2.79; Decrux [Delcrux]
Stars with Bayer designations: e Cru 3.59; ? Cru 4.06; ? Cru 4.14; ?1 Cru 4.32; ?2 Cru 4.72; ? Cru 4.69; ? Cru 5.89; ? Cru 4.62; µ1 Cru 4.03; µ2 Cru 5.08
Stars with Flamsteed designations: 35 Cru; 39 Cru Other notable stars:
* HD 108147 7.00 – has a planet[credit :http://en.wikipedia.org/wiki/Southern_Cross]