ω Centauri
Omega Centauri, a large globular cluster in the constellation Centaurus. A globular cluster is a spherical collection of Stars that orbits a galactic core as a Satellite. Centaurus ( Centaur) is a bright constellation of the southern hemisphere.
Observation data (J2000 epoch)
Class	Globular Cluster
Constellation	Centaurus
Right ascension	13h 26m 45. In Astronomy, an epoch is a moment in time used as a reference for the Orbital elements of a Celestial body. In Astronomy, an epoch is a moment in time used as a reference for the Orbital elements of a Celestial body. The Shapley–Sawyer Concentration Class is a classification system on a scale of one to twelve using Roman numerals for Globular clusters according to their concentration A globular cluster is a spherical collection of Stars that orbits a galactic core as a Satellite. In common usage a constellation is a group of celestial bodies that are connected together in some arrangement typically stars to form a visible figure or picture Centaurus ( Centaur) is a bright constellation of the southern hemisphere. Right ascension (abbrev RA; symbol α) is the Astronomical term for one of the two Coordinates of a point on the Celestial sphere 89s[1]
Declination	-47° 28′ 36. In Astronomy, declination (abbrev dec or δ) is one of the two coordinates of the Equatorial coordinate system, the other being either 7″[1]
Distance	18. 3 ± 1. 1 kly[2] (5. A light-year or light year (symbol ly) is a unit of Length, equal to just under ten trillion Kilometres As defined by 6 ± 0. 3 kpc)
Apparent magnitude (V)	3. History The first direct measurements of an object at interstellar distances were undertaken by German Astronomer Friedrich Wilhelm Bessel in 1838 The apparent magnitude ( m) of a celestial body is a measure of its Brightness as seen by an observer on Earth, normalized to the value 7[3]
Apparent dimensions (V)	36′. 3
Physical characteristics
Mass	~1•1037 kg (~5 000 000[4] M)
Radius	97 ± 6 ly[5]
Estimated age	~12 Gyr[6]
Other designations	NGC 5139,[1] GCl 24,[1] ω Centauri[2]
See also: Globular cluster, List of globular clusters
This box: view • talk • edit

Omega Centauri had been listed in Ptolemy's catalog 2000 years ago as a star. The solar mass is a standard way to express Mass in Astronomy, used to describe the masses of other Stars and galaxies. The New General Catalogue ( NGC) is the best-known catalogue of Deep sky objects in Amateur astronomy. A globular cluster is a spherical collection of Stars that orbits a galactic core as a Satellite. This is a list of Globular clusters. The apparentmagnitude does not include an extinction correction Lacaille included it in his catalog as number I. 5. Omega Centauri or NGC 5139 is a globular cluster of stars seen in the constellation of Centaurus, discovered by Edmond Halley in 1677 listed it as a Nebula. A globular cluster is a spherical collection of Stars that orbits a galactic core as a Satellite. A star is a massive luminous ball of plasma. The nearest star to Earth is the Sun, which is the source of most of the Energy on Earth Centaurus ( Centaur) is a bright constellation of the southern hemisphere. Edmond Halley FRS (ˈɛdmənd ˈhɔːlɪ ( November 8, 1656 &ndash January 14, 1742) was an English Astronomer The English astronomer John William Herschel recognized it first as a globular cluster in the 1830s^[7]. Sir John Frederick William Herschel 1st Baronet KH, FRS ( March 7, 1792 &ndash May 11, 1871)was an It orbits our galaxy, the Milky Way. A galaxy is a massive gravitationally bound system consisting of Stars an Interstellar medium of gas and dust, and Dark matter The Milky Way (a translation of the Latin Via Lactea, in turn derived from the Greek Γαλαξίας (Galaxias sometimes referred to simply One of the few that can be seen with the naked eye, it is both the brightest and the largest known globular cluster associated with the Milky Way. Omega Centauri is located about 18,300 light-years (5,600 pc) from Earth and contains several million Population II stars. In Astronomy and Physical cosmology, the metallicity of an object is the proportion of its matter made up of Chemical elements other than Hydrogen The stars in its center are so crowded that they are believed to be only 0. 1 light years away from each other. It is about 12 billion years old.

Though it is not a star, Omega Centauri was given a Bayer designation. A Bayer designation is a stellar designation in which a specific star is identified by a Greek letter, followed by the genitive form of its parent constellation's Unlike other globular clusters, it contains several generations of stars. It has been speculated that Omega Centauri may be the core of a dwarf galaxy several hundred times its present size, which was ripped apart and absorbed by our Milky Way galaxy. A dwarf galaxy is a small Galaxy composed of up to several billion Stars a small number compared to our own Milky Way 's 200-400 billion stars The Milky Way (a translation of the Latin Via Lactea, in turn derived from the Greek Γαλαξίας (Galaxias sometimes referred to simply A galaxy is a massive gravitationally bound system consisting of Stars an Interstellar medium of gas and dust, and Dark matter Omega Centauri's chemistry and motion in the galaxy is also consistent with this picture. According to new results by the Hubble Space Telescope and the Gemini Observatory, scientists seem to have found an explanation for peculiarities: a black hole at its centre with about 40,000 solar masses. The Hubble Space Telescope ( HST; also known colloquially as "the Hubble" or just "Hubble" is a space telescope that was carried into The Gemini Observatory is an astronomical observatory consisting of two 8-metre Telescopes at different sites A black hole is a theoretical region of space in which the Gravitational field is so powerful that nothing not even Electromagnetic radiation (e The solar mass is a standard way to express Mass in Astronomy, used to describe the masses of other Stars and galaxies. This would also foster the theory that Omega Centauri is a dwarf galaxy^[8].

Like Mayall II, Omega Centauri has a range of metallicities and stellar ages which hints that it did not all form at once (as globular clusters are thought to form) and may in fact be the remains of the core of a smaller galaxy long since captured into the Milky Way. Mayall II ( M31 G1) also known as NGC-224-G1, SKHB 1, GSC 27882139, HBK 0-1, M31GC J003247+393440 In Astronomy and Physical cosmology, the metallicity of an object is the proportion of its matter made up of Chemical elements other than Hydrogen ^[9]

See also

• Sagittarius Dwarf Elliptical Galaxy
• Canis Major Dwarf Galaxy
• Globular Cluster M54
• Mayall II

External links

• Hubblesite - Peering into the core of a globular cluster
• Omega Centauri: Former Core of a Dwarf Galaxy?
• Omega Centauri: Proud Cluster or Sad Remnant?
• Omega Centauri at ESA/Hubble
• Omega Centauri on Wikisky.org

References

---

© 2009 citizendia.org; parts available under the terms of GNU Free Documentation License, from http://en.wikipedia.org
Dapyx Software network: MP3 Explorer | Ebook Manager | Zenithic