Andrew Cooper
Apr 29, 2023    Waikoloa, HI (map)
20cm f/6 Newtonian, Cave Astrola @ 153x
Seeing: 7 Transparency: 6 Moon: 0%

A lovely globular, a swarm of stars filling the field at high power, bright and obvious, visible in the finder, 10' in diameter, fully resolved, a modest concentration to the center, margins notably clumpy, stars 10th magnitude and fainter to the limit of vision, a notable 10th magnitude [HD 151392] on the southern margin 2' from the center

Andrew Cooper
Jun 23, 2020    Waikoloa, HI (map)
20cm f/6 Newtonian, Cave Astrola @ 61x
Seeing: 6 Transparency: 6 Moon: 0%

Large, bright, fully resolved, modest core, three 10th magnitude stars frame the clsuter to the north, south and east, a loose spray of 9-10th magnitude stars trails to the east of the cluster, 3° northwest of M10

Andrew Cooper
Jun 16, 2020    Waikoloa, HI (map)
28cm f/10 SCT, NexStar 11" GyPSy @ 127x
Seeing: 7 Transparency: 6 Moon: 0%

Large at 15', bright, fully resolved, moderately dense at the core, a very nice globular cluster with a bit more aperture

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

Good sized, 15' size fills the 175x field very nicely, bright, fully resolved concentrated core with brilliance rising less sharply to the center much like M10, the bright selection of globulars in Oph make a good evening's viewing, M10 is a little over three degrees southeast

Andrew Cooper
Jun 6, 1998    TIMPA, Avra Valley, AZ (map)
20cm f/10 SCT

As large as M10, but more field stars, well resolved

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

Resolvable. h., 10-16 mg. E. of Rosse, slightly spiral; finely grouped.

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

Captain William Henry Smyth
Aug 11, 1837    No. 6 The Crescent, Bedford, England (map)
150mm f/17.6 refractor by Tully 1827

A fine rich globular cluster, between the right hip and the elbow of Ophiuchus, with a cortège of bright stars, and many minute straggling outliers. This resolvable mass is greatly condensed towards the centre, with several very bright spots: it was discovered by Messier in 1764, but, probably from the imperfection of his means, was registered as "a round nebula, unaccompanied by any star." Its place was obtained by differentiating with ε Ophiuchi from which it is 8°¼ distant, on a north-west-by-west line, leading nearly upon β.

Sir William Herschel resolved this object in 1783; and in the following year his 20-foot reflector made it "a brilliant cluster, 7' or 8' in diameter; the most compressed parts about 2'. By the gauging process, he held its profundity to be of the 186th order.

― A Cycle of Celestial Objects Vol II, The Bedford Catalogue, William Henry Smyth, 1844

John Herschel
Apr 15, 1828    

Very rich globular cluster. The stars are of 10th to 16th magnitude; very gradually much brighter toward the middle, but has stragglers in lines and branches extending some distance from the most condensed part, which is 3' in diameter. Comes almost up to a blaze in the middle, has a star of 10th or 11th magnitude in the centre.

Johann Elert Bode
Aug 14, 1774    Berlin Observatory, Germany (map)

On August 14, 1774, I discovered in Ophiuchus two new nebulae not far from each other. One of them is situated south of 14, 16, 19 and 21 Oph near the western arm, the other below this one and eastward, closely west of 30 Oph. These nebulae appear very pale, and because of this, I found not very reliably the separation to Lambda as 6°7', to the star 14 as 3°50', and to 21 as 3°32'. The other one is separated from the 21st star by 5°32', and by 1°4' from the 30th, as shown in the second figure.

Charles Messier
May 30, 1764    

Nebula discovered in the Serpent, between the arm and the left side of Ophiuchus: this nebula doesn't contain any star, it is round & its light faint; near this nebula there is a star of 9th magnitude. M. Messier has reported it on the second Chart of the Comet observed in 1769. Mem. Acad. 1775, pl. IX. Seen again March 6, 1781.

― Connaissance des Temps, 1781

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

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