Omega Centauri

ω Centauri (Omega Centauri, short ω Cen, also known as NGC 5139 ) is a globular cluster in the constellation Centaurus. He has an apparent diameter of 55 ' and an apparent brightness of 3.9 mag. He is the brightest globular clusters of the sky and already visible with the naked eye as a small patch of fog. It also has the largest absolute magnitude, since it is our Milky Way is by far the most massive globular clusters. Within the Local Group it is in size only by Mayall II, a globular cluster of the Andromeda galaxy, surpassed.

Discoveries

Omega Centauri was discovered in 1677 by the British astronomer Edmond Halley.

Although ω Centauri is not a star, he got a Bayer designation. The object is different from other globular clusters by including multiple stellar populations. Latest researches which have been carried out with the Hubble Space Telescope and the Gemini Observatory, show that it is probably in ω Centauri is a dwarf galaxy that has now been deprived of the Milky Way of stars. The strangeness of this object will now be easier to explain, since you have found a black hole with 40,000 solar masses at the center.

Section of the HST image

Infrared image from the Spitzer Space Telescope