List of open clusters

The open cluster Messier 6 in the constellation Scorpius is also known as the Butterfly Cluster or NGC 6405

This is a list of open clusters located in the Milky Way. An open cluster is an association of up to a few thousand stars that all formed from the same giant molecular cloud. There are over 1,000 known open clusters in the Milky Way galaxy, but the actual total may be up to ten times higher.[1] The estimated half-lives of clusters, after which half the original cluster members will have been lost, range from 150 million to 800 million years, depending on the original density.[2]

Cluster identifier			Constellation	Distance (parsecs)	Age (Myr)	Diameter	Apparent magnitude	Notes
	Epoch J2000
	R. A.	Dec.
Hyades	04^h 26.9^m	+15° 52′	Taurus	47	625	330'	0.5	[3]
Coma Star Cluster	12^h 22.5^m	+25° 51′	Coma Berenices	86	400-500	120'	1.8	[4]
Trapezium Cluster	5^h 35.4^m	−05° 27′	Orion	412	0.3	0.783'	4.0	[5]
Messier 6, Butterfly Cluster	17^h 40.1^m	−32° 13′	Scorpius	487	94	20'	4.2	[1]
Messier 7	17^h 53.8^m	−34° 47′	Scorpius	280	224	80'	3.3	[6][7]
Messier 11, Wild Duck Cluster	18^h 51.1^m	−06° 16′	Scutum	1,900	250	13'	5.8	[1][7][8]
Messier 16, Eagle Nebula	18^h 18.8^m	−13° 49′	Serpens	1,800	1.3	6'	6.0	[1]
Messier 18	18^h 20.0^m	−17° 06′	Sagittarius	1,296	17	5'	6.9	[1]
Messier 21	18^h 04.2^m	−22° 29′	Sagittarius	1,205	12	14'	5.9	[1]
Messier 23	17^h 57.0^m	−18° 59′	Sagittarius	628	300	30'	5.5	[1][7]
Messier 24	18^h 17.0^m	−18° 29′	Sagittarius	3,070	220	90'	2.5	[1][7]
Messier 25	18^h 31.7^m	−19° 07′	Sagittarius	620	92	30'	4.6	[1]
Messier 26	18^h 45.3^m	−09° 23′	Scutum	1,600	85	7'	8.0	[1]
Messier 34	02^h 42.1^m	+42° 46′	Perseus	499	180	36'	5.2	[1][7]
Messier 35	06^h 09.1^m	+24° 21′	Gemini	912	180	25'	5.0	[9]
Messier 36	05^h 36.2^m	+34° 08′	Auriga	1,330	25	10'	6.0	[1]
Messier 37	05^h 52.3^m	+32° 33′	Auriga	1,400	347	14'	5.6	[1]
Messier 38	05^h 28.7^m	+35° 51′	Auriga	1,400	316	20'	6.4	[1]
Messier 39	21^h 31.8^m	+48° 27′	Cygnus	311	280	30'	4.6	[1][6]
Messier 41	06^h 46.0^m	−20° 46′	Canis Major	710	240	40'	4.5	[1][7]
Messier 44, Beehive Cluster	08^h 40.4^m	+19° 41′	Cancer	187	830	70'	3.1	[10][11]
Messier 45, Pleiades	03^h 47.4^m	+24° 07′	Taurus	136	125	120'	1.2	[12]
Messier 46	07^h 41.7^m	−14° 49′	Puppis	1,510	250	20'	6.1	[1]
Messier 47	07^h 36.6^m	−14° 30′	Puppis	490	73	25'	4.4	[1]
Messier 48	08^h 13.7^m	−05° 45′	Hydra	770	400	30'	5.8	[1]
Messier 50	07^h 02.6^m	−08° 23′	Monoceros	1,000	130	14'	5.9	[9]
Messier 52	23^h 24.8^m	+61° 35′	Cassiopeia	1,400	160	15	6.9	[1]
Messier 67	08^h 51.3^m	+11° 48′	Cancer	908	4,000	25'	6.9	[1][7]
Messier 93	07^h 44.6^m	−23° 52′	Puppis	1037	390	10'	6.2	[1]
Messier 103	01^h 33.4^m	+60° 39′	Cassiopeia	3,000	16	5'	7.4	[13]
IC 2602, Southern Pleiades	10^h 43.2^m	−64° 24′	Carina	167	30	100'	1.9	[14]
IC 2391, Omicron Velorum Cluster	08^h 40.6^m	−53° 02′	Vela	176	30	60'	2.5	[14]
NGC 2451 A	07^h 45.4^m	−37° 58′	Puppis	189	50	45'	2.8	[6][15]
Alpha Persei Cluster	03^h 26.0^m	+49° 07′	Perseus	172	50	300'	1.2	[16]
Arp-Madore 2	07^h 38.8^m	−33° 51′	Puppis	8,870	5,000	1.3'		[17]
Blanco 1	00^h 04.3^m	−29° 56′	Sculptor	253	100	90'	4.5	[14]
Hodge 301	05^h 38.5^m	−69° 04′	Dorado	51,400	25	0.5'	11	[18][19]
Lambda Orionis Cluster	05^h 35^m	+09° 56′	Orion	438	5		2.8	[20]
Pi Puppis Cluster	07^h 08^m	−37° 10′	Puppis	319		50'	2.1	[21]
Melotte 186	18^h 01.1^m	+02° 54′	Ophiuchus	200	100	240'	3.0	[22]
NGC 2070	05^h 38.7^m	−69° 06′	Dorado	48,500	1.5	3.5'	7.25	[23][24]
NGC 2232	06^h 26.4^m	−04° 45′	Monoceros	325	53	45'	3.9	[1][6]
IC 4756	18^h 39.0^m	−05° 27′	Serpens	330	500	40'	4.6	[1][6]
NGC 2516, Southern Beehive Cluster	07^h 58.0^m	−60° 48′	Carina	346	141	30'	3.8	[6][7]
IC 4665	17^h 46.3^m	+05° 43′	Ophiuchus	352	43	70'	4.2	[1]
Trumpler 10	08^h 47.8^m	−42° 29′	Vela	365	35	14'	4.6	[1][6]
NGC 6633	18^h 27.7^m	+06° 34′	Ophiuchus	375	660	20'	4.6	[25]
IC 348	03^h 44.6^m	+32° 10′	Perseus	385	44	7'	7.3	[1]
NGC 752	01^h 57.7^m	+37° 47′	Andromeda	400	1,700–2,000	75'	5.7	[26]
NGC 3532, Wishing Well Cluster	11^h 06.4^m	−58° 40′	Carina	405	316	50'	3.0	[6][7]
Collinder 121	07^h 08^m	−37° 10′	Canis Major	600		50'	2.6	[27]
Collinder 140	07^h 24.5^m	−31° 51′	Canis Major	410	35	42'	3.5	[1][6]
Collinder 261	12^h 38.0^m	−68° 22′	Musca	2,500	8,000	9'	10.7	[28][29]
NGC 2547	08^h 10.8^m	−49° 18′	Vela	433	38	25'	4.7	[6]
NGC 6281	17^h 04.7^m	−37° 59′	Scorpius	479	220	8'	5.4	[1]
NGC 225	00^h 43.6^m	+61° 46′	Cassiopeia	657	130	12'	7.0	[1]
NGC 5662	14^h 35.6^m	−56° 37′	Centaurus	666	70	30'	5.5	[1][7]
NGC 5460	14^h 07.4^m	−48° 20′	Centaurus	678	160	36'	5.6	[1][7]
NGC 189	00^h 39.7^m	+61° 04′	Cassiopeia	752	10	3.7'	8.8	[1]
NGC 6025	16^h 03.3^m	−60° 26′	Triangulum Australe	756	130	14'	5.1	[1][7]
IC 5146	21^h 53.5^m	+47° 16′	Cygnus	852	1	9'	7.2	[1]
NGC 2301	06^h 51.75^m	+00° 28′	Monoceros	858	165	12'	6.0	[30]
IC 4651	17^h 24.8^m	−49° 56′	Ara	888	1,900	10'	6.9	[1][7]
NGC 6087, S Normae Cluster	16^h 18.8^m	−57° 56′	Norma	891	70	14'	5.4	[1][7]
NGC 3114	10^h 02.7^m	−60° 07′	Carina	911	124	36'	4.2	[1]
NGC 2509	08^h 00.7^m	−19° 04′	Puppis	912	Uncertain[31]	10'	9.3	[32]
NGC 2264	06^h 41.0^m	+09° 53′	Monoceros	913	1.5	40'	3.9	[33]
NGC 1502	04^h 07.8^m	+62° 20′	Camelopardalis	1,000	10	8'	5.7	[1]
Berkeley 59	00^h 04.0^m	+68° 35′	Cepheus	1,000	2	180'		[34]
NGC 2169	06^h 08.4^m	+13° 58′	Orion	1,052	12	5'	5.9	[1]
NGC 6242	16^h 55.6^m	−39° 28′	Scorpius	1,131	50	9'	6.4	[1][7]
NGC 381	01^h 08.3^m	+61° 35′	Cassiopeia	1,148	320	7'	9.3	[1]
NGC 6204	16^h 46.1^m	−47° 01′	Ara	1,200	79	6'	8.2	[1]
NGC 6231	16^h 54.1^m	−41° 50′	Scorpius	1,243	6	14'	2.6	[1][7]
NGC 2439	07^h 40.8^m	−31° 41′	Puppis	1,300	25	9'	6.9	[1][7]
NGC 6067	16^h 13.2^m	−54° 13′	Norma	1,417	170	14'	5.6	[1][7]
NGC 2362, Tau Canis Majoris Cluster	07^h 18.6^m	−24° 59′	Canis Major	1,480	4–5	5'	4.1	[35]
NGC 6756	19^h 08.7^m	+04° 42′	Aquila	1,507	62	4'	4.5	[1]
NGC 6031	16^h 07.9^m	−54° 03′	Norma	1,510	117	3'	8.5	[1][36]
NGC 2175	06^h 09.7^m	+20° 29′	Orion	1,627	8.9	5'	6.8	[1]
NGC 188	00^h 48.4^m	+85° 15′	Cepheus	1,660	6,600	17'	8.1	[7][37]
NGC 2244	06^h 31.9^m	+04° 56′	Monoceros	1,660	1.9	30'	4.8	[1]
NGC 129	00^h 30.0^m	+60° 13′	Cassiopeia	1,670	76	21′	6.5	[38]
NGC 2360, Caroline's Cluster	07^h 17.7^m	−15° 38′	Canis Major	1,887	1,000	13'	7.2	[1][7]
NGC 6834	19^h 52.2^m	+29° 25′	Cygnus	1,930	76	5'	7.8	[1][36]
NGC 659	01^h 44.4^m	+60° 40′	Cassiopeia	1,938	35	5'	7.9	[1]
NGC 4755, Jewel Box	12^h 53.6^m	−60° 22′	Crux	1,976	14	10'	4.2	[1][7]
NGC 6200	16^h 44.1^m	−47° 28′	Ara	2,056	8.5	12'	7.4	[39]
NGC 869	02^h 19.1^m	+57° 09′	Perseus	2,079	12	18'	3.7	[1]
NGC 637	01^h 43.0^m	+64° 02′	Cassiopeia	2,160	10	4.2'	8.2	[1]
NGC 2355	07^h 17.0^m	+13° 47′	Gemini	2,200	955	5'	9.7	[1][7]
NGC 2129	06^h 01.1^m	+23° 19′	Gemini	2,200	10	5'	6.7	[1][40]
NGC 663	01^h 46.1^m	+61° 14′	Cassiopeia	2,420	25	14'	7.1	[1]
NGC 457	01^h 19.1^m	+58° 17′	Cassiopeia	2,429	21	20'	6.4	[41]
NGC 2204	06^h 15.5^m	−18° 40′	Canis Major	2,629	787	13'	8.6	[1]
NGC 884	02^h 22.0^m	+57° 08′	Perseus	2,940	14	18'	3.8	[1][7]
NGC 1931	05^h 31.0^m	+34° 15′	Auriga	3,086	10	3'	10.1	[1]
NGC 1980	5^h 25.43^m	−05° 54′	Orion	550	4.7	14'	2.5	[42]
NGC 2158	06^h 07.4^m	+24° 06′	Gemini	5,071	1,054	5'	8.6	[1]
Teutsch 2	05^h 41.4^m	+39° 14′	Auriga	5,700	900	2'	11	[43]
NGC 6791	19^h 20.9^m	+37° 46′	Lyra	5,853	8,900	16'	9.5	[1][7]
NGC 3293	10^h 35.8^m	−58° 13′	Carina	2,750	8	8'	4.7
NGC 3766, Pearl Cluster	11^h 36.2^m	−61° 37′	Centaurus	1745	14	12'	5.3
NGC 7419	22^h 54.3^m	+60° 48.9′	Cepheus	2,800		2'	13
NGC 7789, White Rose Cluster	23^h 57.4^m	+56° 43′	Cassiopeia	2,337	1,700	16'	6.7	[44]
Gaia 1	06^h 45.9^m	−16° 45′	Canis Major	4,600	6,300	13'	8.3
Ru 7	06^h 58.9^m	−13° 15′	Canis Major					^[citation needed]

See also

• Lists of astronomical objects
• List of globular clusters
• Lists of clusters

References

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