NGC 6522
Encyclopedia
NGC 6522 is a globular cluster
in the constellation
Sagittarius
. It was discovered by William Herschel on June 24, 1784. It is centered in a region of the sky known as Baade's Window
.
NGC 6522 is possibly the oldest star cluster in the Milky Way
, with an age of more than 12 Gigayears.
Globular cluster
A globular cluster is a spherical collection of stars that orbits a galactic core as a satellite. Globular clusters are very tightly bound by gravity, which gives them their spherical shapes and relatively high stellar densities toward their centers. The name of this category of star cluster is...
in the constellation
Constellation
In modern astronomy, a constellation is an internationally defined area of the celestial sphere. These areas are grouped around asterisms, patterns formed by prominent stars within apparent proximity to one another on Earth's night sky....
Sagittarius
Sagittarius (constellation)
Sagittarius is a constellation of the zodiac, the one containing the galactic center. Its name is Latin for the archer, and its symbol is , a stylized arrow. Sagittarius is commonly represented as a centaur drawing a bow...
. It was discovered by William Herschel on June 24, 1784. It is centered in a region of the sky known as Baade's Window
Baade's Window
Baade's Window is an area of the sky with relatively low amounts of interstellar "dust" along the line of sight from the Earth. This area is considered an observational "window" as the normally obscured Galactic Center of the Milky Way is visible in this direction. It is named for astronomer Walter...
.
NGC 6522 is possibly the oldest star cluster in the Milky Way
Milky Way
The Milky Way is the galaxy that contains the Solar System. This name derives from its appearance as a dim un-resolved "milky" glowing band arching across the night sky...
, with an age of more than 12 Gigayears.