Book contents
- Frontmatter
- Dedication
- Contents
- Foreword
- Preface
- User Guide
- Charles Messier
- The Observations
- The Catalog
- Statistics of the Messier objects
- Visual observation of the Messier objects
- Photography of the Messier objects
- The 110 Messier objects
- M 1
- M 2
- M 3
- M 4
- M 5
- M 6
- M 7
- M 8
- M 9
- M 10
- M 11
- M 12
- M 13
- M 14
- M 15
- M 16
- M 17
- M 18
- M 19
- M 20
- M 21
- M 22
- M 23
- M 24
- M 25
- M 26
- M 27
- M 28
- M 29
- M 30
- M 31
- M 32
- M 33
- M 34
- M 35
- M 36
- M 37
- M 38
- 39
- M 40
- M 41
- M 42
- M 43
- M 44
- M 45
- M 46
- M 47
- M 48
- M 49
- M 50
- M 51
- M 52
- M 53
- M 54
- M 55
- M 56
- M 57
- M 58
- M 59
- M 60
- M 61
- M 62
- M 63
- M 64
- M 65
- M 66
- M 67
- M 68
- M 69
- M 70
- M 71
- M 72
- M 73
- M 74
- M 75
- M 76
- M 77
- M 78
- M 79
- M 80
- M 81
- M 82
- M 83
- M 84
- M 85
- M 86
- M 87
- M 88
- M 89
- M 90
- M 91
- M 92
- M 93
- M 94
- M 95
- M 96
- M 97
- M 98
- M 99
- M 100
- M 101
- M 102
- M 103
- M 104
- M 105
- M 106
- M 107
- M 108
- M 109
- M 110
- Glossary of technical terms
- Index of figures
- Index of sources
M 10
from The 110 Messier objects
Published online by Cambridge University Press: 05 August 2015
- Frontmatter
- Dedication
- Contents
- Foreword
- Preface
- User Guide
- Charles Messier
- The Observations
- The Catalog
- Statistics of the Messier objects
- Visual observation of the Messier objects
- Photography of the Messier objects
- The 110 Messier objects
- M 1
- M 2
- M 3
- M 4
- M 5
- M 6
- M 7
- M 8
- M 9
- M 10
- M 11
- M 12
- M 13
- M 14
- M 15
- M 16
- M 17
- M 18
- M 19
- M 20
- M 21
- M 22
- M 23
- M 24
- M 25
- M 26
- M 27
- M 28
- M 29
- M 30
- M 31
- M 32
- M 33
- M 34
- M 35
- M 36
- M 37
- M 38
- 39
- M 40
- M 41
- M 42
- M 43
- M 44
- M 45
- M 46
- M 47
- M 48
- M 49
- M 50
- M 51
- M 52
- M 53
- M 54
- M 55
- M 56
- M 57
- M 58
- M 59
- M 60
- M 61
- M 62
- M 63
- M 64
- M 65
- M 66
- M 67
- M 68
- M 69
- M 70
- M 71
- M 72
- M 73
- M 74
- M 75
- M 76
- M 77
- M 78
- M 79
- M 80
- M 81
- M 82
- M 83
- M 84
- M 85
- M 86
- M 87
- M 88
- M 89
- M 90
- M 91
- M 92
- M 93
- M 94
- M 95
- M 96
- M 97
- M 98
- M 99
- M 100
- M 101
- M 102
- M 103
- M 104
- M 105
- M 106
- M 107
- M 108
- M 109
- M 110
- Glossary of technical terms
- Index of figures
- Index of sources
Summary
Degree of difficulty 2 (of 5)
Minimum aperture Naked eye
Designation NGC 6254
Type Globular cluster
Class VII
Distance 24,750 ly (Hipparcos, 2001)
Size 140 ly
Constellation Ophiuchus
R.A. 16h 57.1min
Decl. −4° 6′
Magnitude 6.6
Surface brightness –
Apparent diameter 19′
Discoverer Messier, 1764
History Charles Messier discovered M 10 on the 29th of May 1764, just a night after its fainter neighbor M 9, and a night before he found its close neighbor M 12. He observed “a nebula without star” and added: “This nebula is beautiful & round; one can see it only with difficulty in a simple refractor of 3 ft. 4′ diameter.”
20 years later, William Herschel's telescope showed “A very beautiful, and extremely compressed, cluster of stars” and no trace of nebulosity. Herschel compared M 10 with M 53. His son John wrote in 1831: “A superb cluster of very compressed stars, gradually brighter toward the middle. The stars are of 10th to 15th magnitude, and run up to a blaze in the center, but I see no nucleus. Diameter about 6′; a noble object.”
Admiral Smyth used a 5.9-inch refractor and saw a “rich globular cluster of compressed stars. This noble phenomenon is of a lucid white tint, somewhat attenuated at the margin, and clustering to a blaze in the center. Easily resolved with medium magni. cation.” Lord Rosse reported, after his observation with his giant telescope: “A dark lane above the center quite across, or rather the upper one-sixth of cluster is much fainter than the rest.”
The description of Curtis, based on his photographs, says: “Fine bright globular cluster, diameter about 8'. Central brighter part about 2′.”
Astrophysics With a distance of 24,750 lightyears, M 10 is a little farther away than its close neighbor M 12, and its true diameter of 140 light-years is larger than the latter's.
With about 250,000 solar masses, M 10 is a rather average globular cluster.
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- Information
- Atlas of the Messier ObjectsHighlights of the Deep Sky, pp. 95Publisher: Cambridge University PressPrint publication year: 2008