Below is a list of the largest known star clusters, ordered by diameter in light years, above the size of 50 light years in diameter. This list includes globular clusters, open clusters, super star clusters, and other types.
List
+List of largest known star clustersCluster nameDiameter (light-years)Type of clusterNotesPalomar 12324distance × sin( diameter_angle / 2 ) = 162 ly. radiusGlobular clusterAssociated with the Sagittarius Stream, possibly captured from the Sagittarius Dwarf Spheroidal Galaxy. Might be the largest star cluster in the Milky Way.Terzan 7316Within the main body of the Sagittarius Dwarf Spheroidal Galaxy.Messier 54306From trigonometry: radius = distance × sin( diameter_angle / 2 ) = 153 ly.The brightest globular cluster of the Sagittarius Dwarf Spheroidal Galaxy, appears to reside at its core.NGC 339238Located in the Small Magellanic Cloud.Messier 3226Quite isolated at 31.6 kly (9.7 kpc) above the Galactic plane and roughly 38.8 kly (11.9 kpc) from the center of the Milky Way.Messier 11 (Wild Duck Cluster)190Open clusterMessier 2174.4distance × sin( diameter_angle / 2 ) = 87.3 ly. radiusGlobular clusterIn the southern galactic cap of the Milky Way's galactic halo.Omega Centauri172 ± 12distance × sin(diameter_angle / 2), using distance of 5 kpc and angle 36.3′, = 86 ± 6 ly radiusMight be the largest globular cluster in the Milky Way. Possibly a core of an absorbed dwarf galaxy.Messier 13168distance × sin(diameter_angle / 2) = 84 ly radiusMessier 15166distance × sin( diameter_angle / 2 ) = 88 ly radiusPalomar 5152distance × sin( diameter_angle / 2 ) = 76 ly. radiusMessier 75126From trigonometry: radius = distance × sin( diameter_angle / 2 ) = 67 ly.47 Tucanae120distance × sin( diameter_angle / 2 ) = 60 ly. radiusMessier 68106distance × sin( diameter_angle / 2 ) = 53 ly. radiusMessier 22100 ± 10From trigonometry: radius = distance × sin( diameter_angle / 2 ) = 50 lyOne of the first star clusters ever discovered.Messier 14100Messier 6298distance × sin( diameter_angle / 2 ) = 49 ly. radiusMessier 5596From trigonometry: radius = distance × sin( diameter_angle / 2 ) = 17,600 × sin(19′/2) = 48.6 ly.NGC 26594Open clusterMessier 6990From trigonometry: distance × sin( diameter_angle / 2 ) = 28,700 × 0.00157 = 45 ly. radiusGlobular clusterMessier 990Messier 5684From trigonometry: radius = distance × sin( diameter_angle / 2 ) = 32,900 × sin(8.8′/2) = 42.1 ly.Messier 1083.2distance × sin( diameter_angle / 2 ) = 41.6 ly. radiusNGC 320180distance × sin( diameter_angle / 2 ) = 40 ly. radiusMessier 10779From trigonometry: distance × sin( diameter_angle / 2 ) = 39.5 ly. radiusMessier 4675.6Open clusterMessier 475Globular clusterNearest globular cluster to the Earth. Also the first globular cluster known to have exoplanets (PSR B1620-26b)Messier 1274.4distance × sin( diameter_angle / 2 ) = 37.2 ly radiusMessier 7068distance × sin( diameter_angle / 2 ) = 34 ly. radiusNGC 29066Open clusterMessier 2860From trigonometry: radius = distance × sin( diameter_angle / 2 ) = 30 lyGlobular clusterMessier 1852.4Open cluster The following notable star clusters are listed for the purpose of comparison.MGC149 (half-light), 7,800 (tidal)Globular clusterMayall II (half-light), (tidal)Pleiades40.68Open clusterNearest Messier Object to Earth and the easiest to see in the night sky.RSGC2 (Stephenson 2)26.1Alpha Persei cluster22.8Jewel Box20Hyades17.6Nearest open clusterBeehive Cluster (Praesepe)15RSGC19.78 ± 1.96Westerlund 1 (Ara Cluster)6.52Super Star Cluster/Open cluster
See also
List of most massive star clusters
References