Messier 7 - NGC 6475

No dss image available for Messier 7
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Ptolemy's Cluster
Lac II.14, Bode 41, h 3710, GC 4340, Mel 183, Cr 354, C 1750-348

Type  Open Cluster
Magnitude  3.3
Size  80'
Right Ascension  17h 53'  (2000)
Declination  34° 47' S
Constellation  Scorpius
Description  Cl, vB, pRi, lC, *7...12
Classification  II 2 r
Observing Notes

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

A beautiful binocular object, a very bright and coarse cluster over degree across with dozens of 6-8th magnitude stars, resolved, the cluster is visible to the unaided eye, M6 visible one field west

Andrew Cooper
Jun 27, 2020    Waikoloa Quarry, HI (map)
28cm f/10 SCT, NexStar 11" GyPSy @ 80x
Seeing: 7 Transparency: 7 Moon: 0%

Big! bright!! a collection of bright 5-8th magnitude stars that spills well beyond the 0.85° field, coarse, fully resolved, a beautiful object at low power

Andrew Cooper
Jun 29, 2019    Kaʻohe, Mauna Kea, HI (map)
8x42mm Nikon Prostaff 3S Binoculars @ 8x
Seeing: 8 Transparency: 7 Moon: 0%

One of the best binocular objects in the sky, large, bright, rich, fully resolved, a field filled with stars, part of a very rich galactic star field

Andrew Cooper
May 13, 2018    Kaʻohe, Mauna Kea, HI (map)
20cm f/6 Newtonian, Cave Astrola @ 56x
Seeing: 8 Transparency: 7 Moon: 0%

A naked eye cluster, large! bright! coarse, filling the field of the 22mm with bright stars, several dozen blue stars scattered in clumps against the background haze of the Milky Way, a notable mottling of dark nebulae southeast of the cluster

Andrew Cooper
Jun 30, 2010    Keck Observatory, Mauna Kea Summit (map)
76mm f/6 APO, TeleVue-76 @ 14x
Seeing: 7 Transparency: 7 Moon: 0%

A beautiful cluster nicely suited to the wide field of the refractor at low power, bright, coarse, a clump of a couple dozen brighter stars in an incredibly rich starfield

Andrew Cooper
Apr 15, 2007    Pu'u Kuainiho (map)
76mm f/6 APO

Large, Very Bright!! visible to the unaided eye, a coarse assemblage of couple dozen brighter stars (6-9mg.) scattered across a degree of sky

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

Large, extends beyond field, bright stars in a bold arrangement, visible naked eye

John Herschel
May 29, 1835    

A brilliant coarse cluster of the VIII. class [Coarsely scattered clusters of stars], of about 60 stars 7.8....12 m, which fills the field. Irregular figure. A star of 8th magnitude taken.

Charles Messier
May 23, 1764    

A star cluster, more considerable than the preceding [M6]; this cluster appears to the naked eye like a nebulosity; it is little distant from the preceding, placed between the bow of Sagittarius & the tail of Scorpius. (Diam. 30').
― Connaissance des Temps, 1781
Other Data Sources for Messier 7
Nearby objects for Messier 7

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

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Messier 7