Messier 70
Encyclopedia
Messier 70 is a globular cluster
in the constellation
Sagittarius
. It was discovered by Charles Messier
in 1780.
M70 is at a distance of about 29,300 light years away from Earth
and close to the Galactic Center
. It is roughly the same size and luminosity
as its neighbour in space, M69. Only two variable star
s are known within this cluster.
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 Charles Messier
Charles Messier
Charles Messier was a French astronomer most notable for publishing an astronomical catalogue consisting of deep sky objects such as nebulae and star clusters that came to be known as the 110 "Messier objects"...
in 1780.
M70 is at a distance of about 29,300 light years away from Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
and close to the Galactic Center
Galactic Center
The Galactic Center is the rotational center of the Milky Way galaxy. It is located at a distance of 8.33±0.35 kpc from the Earth in the direction of the constellations Sagittarius, Ophiuchus, and Scorpius where the Milky Way appears brightest...
. It is roughly the same size and luminosity
Luminosity
Luminosity is a measurement of brightness.-In photometry and color imaging:In photometry, luminosity is sometimes incorrectly used to refer to luminance, which is the density of luminous intensity in a given direction. The SI unit for luminance is candela per square metre.The luminosity function...
as its neighbour in space, M69. Only two variable star
Variable star
A star is classified as variable if its apparent magnitude as seen from Earth changes over time, whether the changes are due to variations in the star's actual luminosity, or to variations in the amount of the star's light that is blocked from reaching Earth...
s are known within this cluster.