Andrew Cooper
Aug 3, 2023    Waikoloa, HI (map)
28cm f/10 SCT, NexStar 11" GyPSy @ 233x
Seeing: 5 Transparency: 7 Moon: 0%

Very large, very bright, and quite obvious, a blaze of stars abut 12' in diameter, fully resolved with a concentrated core, innumerable stars of 12th magnitude and fainter give the appearance of a celestial firework burst

Andrew Cooper
Jun 27, 2020    Waikoloa Quarry, HI (map)
8x42mm Nikon Prostaff 3S Binoculars @ 8x
Seeing: 7 Transparency: 7 Moon: 0%

Bright, small, not resolved, almost exactly one field (7°) north of πHer

Andrew Cooper
Jun 19, 2020    Waikoloa, HI (map)
28cm f/10 SCT, NexStar 11" GyPSy @ 127x
Seeing: 6 Transparency: 6 Moon: 0%

Bright, decent sized at around 10', fully resolved, the core is quite dense, a very pretty globular cluster

Andrew Cooper
May 12, 2018    Kaʻohe, Mauna Kea, HI (map)
20cm f/6 Newtonian, Cave Astrola @ 102x
Seeing: 8 Transparency: 7 Moon: 0%

A very nice globular, bright, fully resolved, round, about 5' in diameter, a very dense core is at the center of a solid mass of stars

Andrew Cooper
Oct 27, 2006    Waimea, HI (map)
12x36 Canon Image Stabilized Binoculars

Small, bright, round with a bright core, not resolved, more difficult to locate in sparse starfield in the top of Hercules

Andrew Cooper
May 26, 2006    Gila, NM (map)
46cm f/4.5 Deep Violet

Good sized, bright, well concentrated to a dense core, very nice globular so often overshadowed by the nearby M13, it seems to have a sharper rise in brilliance at the core than its competitor

Andrew Cooper
Jun 28, 1998    Santa Rita Mts., AZ (map)
20cm f/10 SCT

Overshadowed by M13, but very similar, many stars resolved, dense core unresolved, but bright

Rev. T.W. Webb
May 19, 1885    Hardwick, Herefordshire, England (map)

Very fine cluster, though not equal to M13; less resolvable; intensely bright in centre. D'A. justly calls it, with his 11-in. achromat at Copenhagen, acervus adsspectu jucundissimuss [a heap of pleasing appearance?]. In H.'s reflectors 7' or 8' diam. Buffam, with 9-in. spec., found stars brighter and more compressed than in M13, but blaze resolved by glimpses. Spectrum as M13. E. of Rosse, possibly spiral, nucleus barely, if at all, resolved.

― Celestial Objects for Common Telescopes, T. W. Webb, 1917

Charles Messier
Mar 18, 1781    

Nebula, fine, distinct, & very bright, between the knee & the left leg of Hercules, it can be seen very well in a telescope of one foot. It contains no star; the center is clear & brilliant, surrounded by nebulosity & resembles the nucleus of a large Comet: its brightness, its size, approach much that of the nebula which is in the girdle of Hercules. See No. 13 of this Catalogue [M13]: its position has been determined, by direct comparison with the star Sigma Herculis, fourth magnitude: the nebula & the star are on the same parallel.

― Connaissance des Temps, 1781

Drawings, descriptions, and CCD photos are copyright Andrew Cooper unless otherwise noted, no usage without permission.

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