U 408
17:12 to 18:00
-39° to -50°
Ara, CrA, Sco
May-Sep

THE CURVE OF THE SCORPIONs tail hosts a fine collection of objects, clusters and nebulae alike.

FEATURED OBJECTS: vdBH 217, vdBH 218, NGC 6318, NGC 6322, Barnard 263, Bernes 150, Harvard 14, IC 4651, NGC 6352, Ru 124, Ru 125, Bernes 151, NGC 6380, ESO333-PN015, NGC 6388, ESO334-SC002, Harvard 17, IC 4663, IC 1266, NGC 6496.

vdBH 217
ESO333-SC002
RA 17:16:06
Dec -40°48.0'
Ocl

vdBH 218

RA 17:16:06
Dec -39°24.0'
Ocl

NGC 6318
Mel 166, Cr 325, Rb 119
RA 17:16:11
Dec -39°25.5'
Ocl

Dunlop 522: "an exceedingly faint nebula, about 1.5' long and 1' broad, elliptical in the direction of the meridian, with two or three very small stars in it."

h: "cluster VII class. Rich, pL, R, gbM, stars 12..14th mag, not a globular."

Steve Coe, observing with a 17.5" f/4.5 at 100X, notes: "Pretty faint, pretty small, pretty rich, somewhat elongated, not much at 100X.

11x80: Scarecely imaginable faint glow, like a globular cluster. (suburban skies) [AS]

NGC 6322
Cr 326, vdBH 220
RA 17:18:28
Dec -42°56.0'
Ocl

h: "coarse B cluster VII. mainly inluded within an equilateral trinagle formed by 3 bright stars 5th and 6th mag. The N.f. of these taken." On a second occassion he called it "vL cluster VII class, of loose stars, on a very rich ground of small stars. The chief star, 6th mag, at the N.f. edge taken."

Steve Coe, observing with a 17.5" f/4.5 at 100X, notes: "Pretty bright, large, not compressed, pretty rich, 25 stars which are shaped like the bow of a ship at 100X. This is a very obscured region of Our Galaxy, there are many dark lanes nearby.

11x80: Clear, equilateral triangle, containing a tight knot of stars. Look for B263 due east. (exurban skies) [AS]

11x80: “Just over a degree east of Eta Sco. While sweeping, appears as three bright (8th mag) stars plus haze. The three bright (white) stars form a neat 7' triangle, within which, especially near the southernmost star, are numerous vS companions. This grouping of large and small stars is noticeable even while scanning the region.” (urban; seeing good; transparency below average; dew) [AS]

Barnard 263
Dark nebula

11x80: “Quite easily seen as an empty patch, elongated NE-SW 1:4. Lies to the west of a noticeable 1° or larger patch of large and 8th magnitude stars, more concentrated and rich than usual starfields. (urban; seeing good; transparency below average; dew) [AS]

Bernes 150
BHe 87
RA 17:21:49
Dec -44°07.9'
Neb

Harvard 14
ESO333-SC007, Tr 25, Cr 329
RA 17:24:28
Dec -39°01.4'
Ocl

IC 4651
Mel 169, Cr 327, Rb 120
RA 17:24:42
Dec -49°56.3'
Ocl

This open cluster was recorded by Bailey of Harvard College Observatory, who described it simply as a pretty compressed cluster.

Trumpler (Lick Obs Bul, Vol 14, No. 420) gives the diameter as 14' and the class as 2 2 r.

Hartung calls it "an irregular gathering of numerous stars fairly uniform in brightness, about 15' across with stragglers to 20'. The stars are in lines, curves and chains enclosing dark spaces so that the pattern is open without much condensation. 15cm is needed to show the cluster well."

Sanford notes that it is an open cluster with about 80 stars brighter than 9th magnitude and about 15' across, demanding telescopic views at low powers.

Phil Harrington (1990, Touring the Universe through Binoculars) writes that it "may be found just west of 3rd mag Alpha Area. Observers should find this open cluster a fairly easy catch. Its 70 stars combine to 7th mag and are concentrated across 12' of arc. However, only the largest glasses are above to resolve any of them individually, as the brightest are only 11th mag."

10x50: 17' wide, brightness uneven, 3 stars resolved in the cluster (suburban skies) [RH]

11x80: This open cluster is easy to spot in 11x80 binoculars, appearing as an even, misty patch one degree west of Alpha Ara. A remarkable patch of mottled milky light, estimated 12' across, fanning out widely from a 9th mag star, then fading insensibly into the background. The 9th mag star lies on the northwestern edge of the cluster. (suburban skies) Large, round (or slightly elongated) patch of extremely fine star-points. Grainy. Readily seen. Very nice! (suburban skies) [AS]

11x80: “Wow! Makes me think of the Helix. In a field with a number of brightish paired stars, lies this faint, large (16') irregularly-round patch, mottled, with three small stars made out; brightest to its eastern side. A surprisingly large but delicate object - beautiful.” (urban; seeing good; transparency below average; dew) [AS]

6-inch f/8.6 Newtonian: “Obvious in the sweeper (45x, 50' field of view), I examined this 10' cluster at 52x, which shows it as a very open grouping, reasonably separated from the background. At least 40 stars are easily seen (at 104x), with fainter ones adding a background glow to the group; this makes it appear like a well-resolved globular (like M4 in the 15.5-inch). The cluster’s light is gathered into discrete clumps and groupings, with dark patches between. At this power (104x) I’m inclined to think the cluster is about 15' across.” (exurban, lim mag 6.2 naked eye; seeing good; dew!) [AS]

15.5-inch f/9 Newtonian: Easy; a very spread out, barren cluster of stars, not well detached from the background. The cluster seems to have a roughly triangular nucleus made up of about 15 stars. Surrounding this central core are dark star-less patches which almost isolate the nucleus from the rest of the cluster members. The cluster, then, has the appearance of an irregular ring of stars, inside of which lies the triangular core. There are two prominent dark patches, one to the west and the other to the northeast of the nucleus. These two voids look somewhat like a pair of lungs! (suburban skies) [AS]

NGC 6352
ESO228-SC003
RA 17:25:29
Dec -48°25.0'
Gcl

Dunlop 417: "a rather faint nebula, or an irregular round figure, 4' diameter, slightly branched; easily resolvable into stars, with slight compression of the stars to the centre."

It was also reported by Barnard, who observed with a 6-inch refractor at Nashville, Tennessee.

The NGC calls it only "pretty faint, large." In the 'Notes and Corrections to the New General Catalogue', Stewart notes: "a cluster, not a nebula." It is remarkable that John Herschel did not find this cluster during his methodical sweeps of the southern sky.

Hartung writes "In this fine field sown profusely with stars is one of the less-condensed type of globular cluster, irregularly round, about 2.5' across and resolved into very faint stars, some of which can be seen with a four-inch scattered through the haze and the outlying region. It is surprising that John Herschel's thorough sweeping missed this conspicuous object."

Gerd Bahr-Vollrath (Noosa Heads, Queensland, Australia) observing with an 8-inch f/12 SCT, writes in the The Webb Society Nebulae and Clusters Section Report No. 10, July 1992: "Fairly small round glow. Only a slight increase in brightness towards the core. Appears grainy throughout."

RA 17 25 29.2 (2000) Dec -48 25 22 Integrated V magnitude 7.96 Central surface brightness, V magnitudes per square arcsecond 18.42 Integrated spectral type G4- Central concentration, c = log(r_total/r_core); a 'c' denotes a core-collapsed cluster 1.10 Core radius in arcmin .83. ["Catalog Of Parameters For Milky Way Globular Clusters", compiled by William E. Harris, McMaster University. (Revised: May 15, 1997; from http://www.physics.mcmaster.ca/Globular.html; Harris, W.E. 1996, AJ, 112, 1487) ]

11x80: F, R, 4.5' glow, light evenly spread out, no fringe. Requires care if it is to be singled out from a diverse field. (urban; seeing good; transparency below average; dew) [AS]

8-inch f/6.7 Newtonian, 9.7mm eyepiece: "Very faint, it is better seen with averted vision or slightly shaking the telescope. High power required." [GG]

8-inch Meade, Super wide-angle, 18mm eyepiece,36' fov: Large, bright, irregular round globular cluster, not very dense. Faint stars scattered through the haziness. Brighter stars group together outside to the south. [MS]

Ru 124
ESO333-SC?009
RA 17:27:56
Dec -40°43.4'
Ocl

Ru 125
ESO333-SC010
RA 17:29:38
Dec -40°27.6'
Ocl

Bernes 151
BHe 91
RA 17:34:00
Dec -39°24.0'
Neb

NGC 6380
Pismis 25, GCL-68, Ton 1
RA 17:35:24
Dec -39°04.0'
Gcl

h: "a star 9th mag, with an eF nebulous wisp or tail, extending northwards about 1'." On a second occassion he called it "a star 9th mag with a very evident eF nebulous wisp 1.5' long, 30 arcseconds broad. (The wisp by the diagram is fan-shaped, and extends in the N.p. direction from the star. See fig 18, Pl VI.)"

Burnham describes it as very small, extremely faint, diameter 2', stars of magnitude 16 and fainter with 8.5 magnitude star of southern edge.

Steve Coe, observing with a 17.5" f/4.5 at 100X, notes: "Very, very faint, very small, not brighter in the middle, round at 165X. Appears like a double star at low power. At 220X it is 30" in size, round, and needs averted vision and good seeing to pick this very obscured globular out of the Milky Way. My friends and I are convinced that Wil Tirion included it on his Sky Atlas as a challenge object.; 36" f/5 TSP 96 7/10 S+T Not much with 36" of aperture, somewhat brighter middle. 6 stars resolved. "King of the little turd globulars".

See Sky & Telescope, July, 1984, p88: "NGC 6380: An elusive globular cluster." by James Meketa.

RA 17 34 28.0 (2000) Dec -39 04 09 Integrated V magnitude 11.31 Central surface brightness, V magnitudes per square arcsecond 19.96 Integrated spectral type Central concentration, c = log(r_total/r_core); a 'c' denotes a core-collapsed cluster 1.55c: Core radius in arcmin .34. ["Catalog Of Parameters For Milky Way Globular Clusters", compiled by William E. Harris, McMaster University. (Revised: May 15, 1997; from http://www.physics.mcmaster.ca/Globular.html; Harris, W.E. 1996, AJ, 112, 1487) ]

15.5-inch f/9 Newtonian: Searched for this one a coupla times, once with a friend, at around 220x; nothing but a star of about 10.5 mag. (suburban skies) [AS]

ESO333-PN015
Le - 16
RA 17:35:41
Dec -40°11.4'
Pln

NGC 6388
ESO279-SC002
RA 17:36:17
Dec -44°44.0'
Gcl

Dunlop 457 "a beautiful round nebula, about 5' diameter, with a bright round well-defined disk or nucleus, about 15 arcseconds diameter, exactly in the centre; this has the appearance of a planet surrounded by an extremely faint diluted atmosphere; there is a small star involved in the faint atmosphere: the atmosphere is at least 6' diameter."

h: "globular, vB, R, first p g, then psvmbM, 4' diam, easily resolved with left eye into stars 17th m, more difficulty with right eye into 18m, ecessively close and comp; shading off insensibly in borders into the general ground of the heavens." On a second occassion he called it "globular, vB, R, at first pg, then psvmbM to an intense almost nuclear light. The right eye does not resolve or barely makes it resolvable; the left resolves it completely into stars 17..20m. A superb object on a rich ground of milky way."

Steve Coe, observing with a 17.5" f/4.5 at 100X, notes: "Bright, pretty large much brighter in the middle, 6 stars resolved at 165X. This globular was seen in the finderscope.

RA 17 36 17.0 (2000) Dec -44 44 06 Integrated V magnitude 6.72 Central surface brightness, V magnitudes per square arcsecond 14.55 Integrated spectral type G2 Central concentration, c = log(r_total/r_core); a 'c' denotes a core-collapsed cluster 1.70 Core radius in arcmin .12. ["Catalog Of Parameters For Milky Way Globular Clusters", compiled by William E. Harris, McMaster University. (Revised: May 15, 1997; from http://www.physics.mcmaster.ca/Globular.html; Harris, W.E. 1996, AJ, 112, 1487) ]

11x80: (strong moonlight): Midway between Theta Sco and Sigma Ara within a very busy field lies this small, distinct globular, not washed out by the strong moon. It has two 'antennae' stars, to the south-east and north-east. (suburban skies) [AS]

11x80: “Like a dewed-up 8th magnitude star, one of a number of 7th-8th mag stars around. The cluster is B, 5' across, R, like a typical globular in binoculars. Has almost no fringe and an even brightness distribution; just like a fuzzy planet. Easy to see.” (urban; seeing good; transparency below average; dew) [AS]

8-inch Meade, 18mm eyepiece; 36' fov: Very bright, large round globular cluster, with a sudden compressed bright core. Well-resolved clear stars up to the fringes. A bright star taking side out to the north and another one to the south in the starfield. Excellent object in a beautiful starfield. A little smaller than NGC 6362. (suburban skies) [MS]

8-inch f/6.7 Newtonian, 9.7mm eyepiece: "Bright, clearly seen in a wide field ocular. Not resolved into stars." [AS]

ESO334-SC002

RA 17:36:55
Dec -42°13.6'
Ocl

Harvard 17
ESO334-SC004, Tr 29, Cr 343
RA 17:41:29
Dec -40°09.1'
Ocl

IC 4663
ESO279-PN006, PK346-08.01
RA 17:45:27
Dec -44°43.0'
Pln

Also known as Fleming 97, this planetary was discovered by Fleming at Harvard Observatory on the basis of its spectrum.

Burnham calls it "13th magnitude, small, very faint and appears nearly stellar with a diameter of only 15 arc seconds."

Steve Coe, observing with a 17.5" f/4.5 at 100X, notes: "Faint, pretty small, round, greenish dot at 165X. Averted vision makes it grow.

IC 1266
ESO279-PN007, PK345-08.01
RA 17:45:34
Dec -46°05.4'
Pln

NGC 6496
ESO279-SC013
RA 17:59:00
Dec -44°16.0'
Gcl

h: "a distinctly nebulous insulted group, mE, 2' long, 1.5' broad, many stars of considerable size, mixed." On a second occassion he called it "Cluster very rich, irregularly round, including to triangular; vglbM, 4' or 5' diam, with many large and small stars in it. Nebulous."

Bailey, examining a Bruce plate (Harvard Annals, Vol 72, No 2), describes it as "Coarse cluster of half a dozen pretty bright stars, on background of faint stars, or nebulosity."

Hartung notes: "This globular cluster belongs to the most open type of these objects; 30cm discloses a faint roundish haze about 2' across without central condensation. Some faint stars may be seen in it but these may be field stars as the surrounding region is well sown. The cluster is shown by 10.5cm as a dim, hazy spot."

RA 17 59 02.0 (2000) Dec -44 15 54 Integrated V magnitude 8.54 Central surface brightness, V magnitudes per square arcsecond 20.10 Integrated spectral type G4- Central concentration, c = log(r_total/r_core); a 'c' denotes a core-collapsed cluster .70 Core radius in arcmin 1.05. ["Catalog Of Parameters For Milky Way Globular Clusters", compiled by William E. Harris, McMaster University. (Revised: May 15, 1997; from http://www.physics.mcmaster.ca/Globular.html; Harris, W.E. 1996, AJ, 112, 1487) ]

11x80: Seen as a blurry star, a small patch of extended light. (suburban skies) [AS]

12-inch Meade, 40mm eyepiece, 53' fov.: Faint large elongated haze of light. I could not make out any core. Stars spread out towards the edges of this globular cluster, which looks more to me, like an open cluster. A bright orange star is visible towards the edge of the starfield. [MS]