Messier 70 | |
---|---|
![]() Globular cluster Messier 70 by
Hubble Space Telescope; 3.3′ view | |
Observation data ( J2000 epoch) | |
Class | V [1] |
Constellation | Sagittarius |
Right ascension | 18h 43m 12.76s [2] |
Declination | –32° 17′ 31.6″ [3] |
Distance | 29.4 kly (9.0 kpc) [4] |
Apparent magnitude (V) | 7.9 [5] |
Apparent dimensions (V) | 8.0 ′ [6] |
Physical characteristics | |
Mass | 1.79×105 [4] M☉ |
Radius | 34 ly [7] |
Tidal radius | 11.2′ [8] |
Metallicity | = –1.35 [9] dex |
Estimated age | 12.80 Gyr [9] |
Other designations | GCl 101, M70, NGC 6681 [3] |
Messier 70 or M70, also known as NGC 6681, is a globular cluster of stars to be found in the south of Sagittarius. [a] It was discovered by Charles Messier in 1780. [b] [6] The famous comet Hale–Bopp was discovered near this cluster in 1995. [10] [c]
It is about 29,400 [4] light years away from Earth and around 6,500 light-years [11] from the Galactic Center. It is roughly the same size and luminosity as its neighbour in space, M69. [12] M70 has a very small core radius of 0.22 ly (0.068 pc) [13] and a half-light radius of 182.0 ly (55.80 pc). [14] This cluster has undergone core collapse, leaving it centrally concentrated [15] with the luminosity distribution following a power law. [11]
There are two distinct stellar populations in the cluster, with each displaying unique abundance abundances. These likely represent different generations of stars. [16] Five known variable stars lie within the broadest radius, the tidal radius, of it, all of which are RR Lyrae variables. [8] [17] The cluster may have two blue stragglers near the core. [11]
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citation}}
: CS1 maint: multiple names: authors list (
link)
Messier 70 | |
---|---|
![]() Globular cluster Messier 70 by
Hubble Space Telescope; 3.3′ view | |
Observation data ( J2000 epoch) | |
Class | V [1] |
Constellation | Sagittarius |
Right ascension | 18h 43m 12.76s [2] |
Declination | –32° 17′ 31.6″ [3] |
Distance | 29.4 kly (9.0 kpc) [4] |
Apparent magnitude (V) | 7.9 [5] |
Apparent dimensions (V) | 8.0 ′ [6] |
Physical characteristics | |
Mass | 1.79×105 [4] M☉ |
Radius | 34 ly [7] |
Tidal radius | 11.2′ [8] |
Metallicity | = –1.35 [9] dex |
Estimated age | 12.80 Gyr [9] |
Other designations | GCl 101, M70, NGC 6681 [3] |
Messier 70 or M70, also known as NGC 6681, is a globular cluster of stars to be found in the south of Sagittarius. [a] It was discovered by Charles Messier in 1780. [b] [6] The famous comet Hale–Bopp was discovered near this cluster in 1995. [10] [c]
It is about 29,400 [4] light years away from Earth and around 6,500 light-years [11] from the Galactic Center. It is roughly the same size and luminosity as its neighbour in space, M69. [12] M70 has a very small core radius of 0.22 ly (0.068 pc) [13] and a half-light radius of 182.0 ly (55.80 pc). [14] This cluster has undergone core collapse, leaving it centrally concentrated [15] with the luminosity distribution following a power law. [11]
There are two distinct stellar populations in the cluster, with each displaying unique abundance abundances. These likely represent different generations of stars. [16] Five known variable stars lie within the broadest radius, the tidal radius, of it, all of which are RR Lyrae variables. [8] [17] The cluster may have two blue stragglers near the core. [11]
{{
citation}}
: CS1 maint: multiple names: authors list (
link)