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RA: 06h 46m 0s
Dec: −20° 46′ 0″
Con: Canis Major
Ch: MSA:322, U2:318, SA:19
Ref: SIMBAD, Collinder (1931), DAML02, Archinal&Hynes (2003)
Type: open cluster, 13r
Mag: B=4.89, V=4.5
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In the Appendix to the 1912 'Scientific Papers of Sir William Herschel' this object is described as "1784, October 20, 20 feet telescope, a large cluster of very coarsely scattered large stars."
Observations with the 72-inch f/8.8 speculum telescope at Birr Castle noted "Nov 25, 1851. A coarse bright cluster."
In the 5th edition of Webb's Celestial Objects for Common Telescopes it is described as "superb group, visible to naked eye. Four degrees beneath Alpha. Larger stars in curves, with ruddy star (Espin: variable?) near centre, 5.5-inch ."
Bailey, S.I. (1908) A catalogue of bright stars and nebulae. Ann.Harv.Coll.Obs., 60(8), 199.
Raab, S. (1922) A research on open clusters. Lund Medd. Astron. Obs. Ser. II, 28, 1.
Discussed, based of F-A plates.
A catalogue of star clusters shown on Franklin-Adams chart plates. Mem.R.A.S., 60(5), 175-186.
Trumpler (Lick Obs Bul, Vol 14, No. 420) gives the diameter as 32' and the class as 1 3 r.
Burnham calls it a fine bright cluster, visible to the naked eye and partially resolvable in field glasses. It is a "beautiful object in low power instruments, and is a favourite of deepsky observers. It contains about 25 bright stars and many fainter ones ... there is a bright reddish star near the centre; many of the other stars seem to be arranged in curving rows and groups. ... M41 was stated by C.E. Barns to be "possibly the faintest object recorded in classical antiquity"; it was mentioned by Aristotle about 325 B.C.as one of the mysterious 'cloudy spots' then known in the sky. Approximately 100 stars are now recognized as true members of this cluster, ranging in brightness from 7th to 13th magnitude." The brightest member is a K3 II star of 6.93 magnitude, which is the central reddish star. The third brightest star is a type K1 II (7.46 mag), the fifth brightest is type K0 II (7.82 mag) and the sixth brightest is a type K4 II (7.87 mag).
Sanford notes that this cluster is "visible to the naked eye, located where you would find the dog's heart. It contains several fairly bright stars and multiples. The cluster is almost half a degree in diameter."
Doig, P. (1925) Notes on the nebulae and clusters in Webb's 'Celestial Objects for Common Telescopes' (Sixth edition, Vol.ii). Part I. M.N.R.A.S., 35(5), 159.
Vorontsov-Velyaminov, B. (1925) "Catalogue of integrated magnitudes of star clusters", Astron. Nach. 226.195. Comparing the brightness of the cluster with the extrafocal images of stars, he estimates the magnitude as 5.91.
Doig, P. (1926) "A Catalogue of Estimated Parallaxes of 112 Nebulae, Open clusters and Star Groups", Vol 36 (4), p 107-115.
"open, well-defined cluster visible to naked eye." He gives the approx. diameter as 37 arcmin.
The RNGC (Sulentic and Tifft 1973) notes that this is a 5.0 mag open cluster.
Hartung calls this a fine cluster, noting the presence of "some delicate pairs and triplets with a fine yellow star near the centre."
Harrington notes that this "dazzling" cluster is visible to the naked eye on any dark night. He writes: "Even through a veil of light pollution, low-power binoculars should pick up about two dozen of the cluster's stars. Telescopes show M41 bursting with splendor. The brighter members create a central keystone asterism strongly resembling that of the constellation Hercules. An added bonus, many of M41's stars form closely tied pairs or triplets. By slightly defocusing the telescope's image, many will shine with hints of yellow, orange, and blue-white. Most of the suns are crammed within a half-degree circle, though some stragglers lie farther out."
Houston notes that he has easily seen this cluster with the naked eye and that it is brighter than M11 in Scutum. He adds: "Telescopically, it shows curved lines of stars."
Tom Lorenzin, in the electronic version of "1000+ The Amateur Astronomers' Field Guide to Deep Sky Observing", notes: "4.5M; 38' diameter; large but sparse; best in 1 degree field at low-x; 6M star at S edge is 12 CMA; 4 degrees S and a little E of Sirius (Alpha CMA); good binocular object."
Donald J. Ware:"Large and splashy, this fine open cluster is easily seen as a hazy patch to the naked eye, and is fully half a degree in diameter in the telescope. About 60-70 stars can be seen at low power, in many curving chains. The cluster is dominated by a bright orange star near its center. A great open cluster."
Observer: Alan Shaffer (e-mail: firstname.lastname@example.org)
Instrument: 10-inch Schmidt-Cassegrain reflector Location: Redondo Beach, CA, USA
Light pollution: moderate Transparency: good Seeing: fair
Time: Mon Feb 10 04:00:00 1997 UT Obs. no.: 65
Easy view. My setting circles were right on!! Used 24.5 SWA at 2500mm. See 20-30 brightest stars and many more faint stars. Nice circular cluster. Espin star has a red glow!!
Observer: John Callender
Instrument: 50-mm binoculars Location: Carpinteria, CA, USA
Light pollution: light Transparency: good Seeing: fair
Time: Wed Feb 5 05:20:00 1997 UT Obs. no.: 55
Big, bright cluster; about 10 members visible in binoculars. A fairly easy fuzzy patch with the naked eye.
AJ Crayon, using an 8" f/6 Newtonian, notes: "(M 41) an open cluster that is visible in an 8X50 finder that has 10 stars involved in a bright glow. At 120X it is 7m 30' has 60 stars from 8m to the 14m limit of the telescope.
Observer: Todd Gross Your skill: Intermediate Date and UT of observation: 12/30/97 07:30 GMT Location & latitude: Cancun, Mexico Site classification: Urban/Suburban Limiting magnitude (visual): 4.6 zenith (est) 4.5 (est) in vicinity of object Seeing (1 to 10 - worst-best): unknown - 5? Moon up (phase?): No Weather: Clear to pt. cloudy Instrument: 80mm APO refractor f/6 - f/l 480mm Magnifications: 16x,32x, 69x Personal Rating (for this aperture): B
Very nice to view so high in the sky from this (relatively) southern locale. A moderately rich, large cluster, very easy to pick up in 8x32 binoculars. In the scope..medium-bright stars, about 50 of them, many equal in brightness, but some weaker members as well. Showed best at around 30x. Took up nearly the entire field of view at 32x (52 deg apparent field size) It was not round, but elongated somewhat, seemingly oriented SE-NW.
Steve Coe, using a 17.5" f/4.5, notes: "(M41) bright, large, somewhat compressed, 60 members with orange star in center. Many curved lines of stars at 100X. Easily seen in 8X50 finder."
6cm - sketchin logbook. BS, 5Oct1969, FtL.
- 29 *s seen @ 35x. fine, br obj for sm tele.
- band of *s on NW.
7cm - lg br rich cl @ 30x sim to Messier cls in Aur, but much brtr *s. outliers reach to 12 CMa on SE, or 45' diam. in this area are 125 *s w/mod concen across center @ 50x. two wide pairs (one br, one f) on NW side of core, another closer pair isolated to NNE side. BS, 26Nov1992, Anderson Mesa.
15cm - typical br cl. 50 *s in 30' area, m7-11. m6 * on SE edge.
25cm - 45' diam. second brtst * NE of center has strange-looking companion. m6 * SE. center mostly vacant. on W side are many fntr *s.
30cm - sev pairs noted.
Danie Cronje, observing with 10x50 binoculars, notes "contains a few bright stars, especially two in centre of cluster. The rest is fainter and shows better with averted vision. An unresolved element remains. With averted vision a central bar is seen, with another (shorter) one on the left."
This is a beautiful cluster in any instrument; in a 10-inch f/5 at 30x it appears to span over almost 3/4 of a degree. It is well spread out and yet stands out well as a fine group. It has a dozen or so really bright members, the rest of the members fading away as they grow dimmer. To the side of the cluster, just off centre, lie two stars which appear to be slightly red; the outermost one more prominent. The stars right in the centre form a semi-circular grouping of about 7 members.
Observing from the 1500 metre plateau of the SAAO observing site in Sutherland, I was surprised at the ease with which this cluster could be seen with the naked eye - it is an easy small patch of light in the CMa milky way.
Sutherland (Ouberg Quarry)
11x80 tripod mounted binoculars
Conditions: NELM: fainter than 6.0 at the S.pole
Large cluster of a dozen brighter stars, with great many more fainter ones scattered amongst them. Lies on a very rich Milky Way field, from which it is only modestly separated. Two bright copper-coloured stars at the centre. Rough sketch made (not reproduced). Two copper-coloured stars refered to are HD 49126 (B-V=+0.56) and HD 49091 (B-V=+1.5). The colour index of the former does not seem to be very red, however. Used Uranometria chart 390 to locate.
Telescope: Meade 12-inch - 40mm wide-angle eyepiece.
Date: 18th January 1999.
Beautiful, large and bright cluster of stars, appearing like a rose with curled petals that fold out into distinct loops and chains of stars. Prominent red star within the reasonably compact nucleus has a number of bright stars nearby, looking like the pollen-tube of a flower, extending outwards. The bright 12 Canis Majoris lies to the south-east.
Date and Time: 18 May 2009, 19:20
Location: Prince Albert (Western Cape, South Africa).
Instrument: Skywatcher 90mm (3.5") f/10 Achro Refractor
Eyepieces: 25mm (36x, 1.4� FOV)
Sky Conditions: Seeing: 5/10. Transparency: Average
36x: Large open cluster approximately 40′ in size. Easy to see. About 70 stars of mixed brightness counted. Slight concentration towards center. 2 rows of 3 stars in the SW edge pointing in a W to E direction. 1 row of 5 stars in the center of the cluster pointing in W to E direction. 2 bright stars visible at the SE edge. Other stars form curves and clumps.
Sky Conditions: Poor: Cloudy
Quality of Observation: Moderate
6" Dobsonian, 25mm & 10mm Eyepieces
Clearly visible with the naked eye, the Little Beehive open cluster appears as a very small cloudy object north east of Sirius. At 48x magnification the loosely arranged stars become more apparent, but at 120x magnification the image is not as magnificent due to the high magnification and much of the beauty of this cluster is lost together with the background stars. The Little Beehive is comprised of several bright stars one can distinguish the dim colours of the various stars. Giving much the impression of M44 (Beehive Cluster) only at a smaller scale, it still remains just as impressive as its larger counterpart.
Date: 2006 12 22, 21:30
Instrument: 8-inch Dobsonian, 25mm eyepiece
Sky:Clear, light pollution
Notes: Open cluster. Large, almost filling the eyepiece. Many stars similar in brightness. There is a bright orange star near the centre.
Instrument:12-inch Dobsonian Reflector Telescope.
Eyepieces:26mm Super Wide Field Eyepiece, 20mm Ultra Wide Angle Eyepiece.
Sky Conditions:The fainter parts of the Milky Way are barely visible.
Transparency of the Sky:Haziness only visible on the horizon.
Seeing:Atmosphere stable with little interference.
Chart Number:No.26(Extract taken out of "Star Gazer's Deep Space Atlas").
First Impression: This object looks like a large open cluster.
Size in Arc Minutes: 26.7'.
Brightness Profile: This open cluster is bright all over.
The brightness of the stars in this open cluster shines like bright diamonds in the night sky. Towards the centre of this open cluster I noticed a bright orange star. In overall I have estimated 180 stars in this open cluster.
Location: Riviera, Pretoria
Telescope: Orion 10 In Dob
Limiting magnitude: 4.5
Sky conditions: Good seeing and transparency
A Sparkling group of stars. Different magnitudes clearly identifiable. More faint stars become visible through adverted vision. There is a variety of geometrical patterns
Observing site: Pinnacles overlook
[6h 47m 0s, -20� 44' 0"] A large, loose cluster of bright white stars. Nice.
Location: Bonnievale SSP (Night Sky Caravan Park)
Binoculars: Canon 12x36 IS (5-deg fov)
Sky conditions: Good (8/10)
Quality of observation: Good
M 41 is a large open cluster (too large for 0.57-deg eyepiece). Triangular shape pointed to West.
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