NGC 253 Ben 4 ESO474-G029 RA 00:47:34 Dec -25°17.5' Galaxy
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Nicknamed the Silver Coin or Sculptor Galaxy,
it is probably Caroline Herschel's most spectacular discovery.
At the Cape, h's first record of it was made
on 20 November 1835. He recorded it as "very very bright; very very large;
very much elongated; 30' long, 3' or 4' broad; has several stars in it;
gradually much brighter towards the middle to a centre elongated like the nebula
itself. The nebula is somewhat streaky and knotty in its constitution and may
perhaps be resolvable." A second observation made on 12 September 1836 was
recorded as "very very bright; very very very large; a superb object; 24'
in length, breadth about 3'; posn = 143.8 very exact. Its light is somewhat
streaky, but I see no stars in it but 4 large and one very small one, and these
seem not to belong to it, there being many near. - The difference of R
Ascensions of this and the former obs. arises in great part from the undefined
nature of the object."
Houston calls it a "bright, highly
inclined spiral that resembles NGC 55 in magnitude and size. One difference is
that the illumination is more evenly distributed across the disk. Caroline
Herschel discovered it while searching for comets. It stands as a tribute to her
comet hunting career, since only a truly dedicated observer would search the
dregs of the atmosphere as near to the horizon as NGC 253 appeared from her home
in England." In 1976 he wrote: "NGC 253 is a fine spiral galaxy that
appears as a bright 24'x4' oval."
Mullaney writes that is "can easily be
glimpsed in binoculars and finders from northern temperate latitudes despite its
southern declination. ... It is a real showpiece in 6-inch and larger
telescopes."
William P. Clarke (San Diego, California, USA)
writes in the The Webb Society Nebulae and Clusters Section Report No. 10, July
1992: "Large and highly elongated galaxy with a bright nuclear region, and
strong mottling throughout. A pair of 8th magnitude stars are just south of the
nucleus. (10-inch f/4.5, x48)."
Steve Coe, in "SACNEWS On-line for
November 1996" notes: NGC 253 is one of the most beautiful galaxies in the
sky. Every astrophotographer who can get at this lovely, bright edge-on will
shoot it eventually. It can be seen at 0 hr 47.6 min and -25 17. On a night at
Sentinel that I rated 9/10 for transparency and 8/10 for seeing it was a
stunning site in a variety of instruments. This bright object was easy in
binoculars or finderscope and 1 star on NE end and 3 stars on the southwest end
frame the galaxy. At 60X with a 38mm Erfle eyepiece in my 13", I saw NGC
253 as very bright, very large, very much elongated 4X1 in PA 45, much brighter
middle, very mottled, a beautiful convex lens shape, with many dark markings in
arms. Going to 100X provided an excellent view, with a stellar nucleus evident
about 20% of the time, 7 stars involved, two pretty bright oval patches in
southwest arm, and lots of dark markings, the most mottling I have ever seen.
Michael E. Sweetman (Tucson, Arizona, USA),
observing with a 12x40 binoculars, writes in the The Webb Society Nebulae and
Clusters Section Report No. 10, July 1992: "Easily spotted at x48. Large
and bright but with hazy edges; there is no nuclkeus and only a slight increase
in brightness towards the centre. Best views obtained at x102; several star-like
points scattered across the image. The galaxy is elongated east-west; the
extremities are faint and averted vision shows how extremely large it is. The
preceding side is brighter and more well-defined; following side very hazy.
Uneven brightness around the centre, which shows some mottling."
Listed by the Herschel Club, described as "extremely
elongated, a band of light or streak across the eyepiece field, covering 30
arcsec across. Bright in centre, fading towards the outer rim. 8-inch, 48x."
Tom Lorenzin, in the electronic version of "1000+
The Amateur Astronomers' Field Guide to Deep Sky Observing", notes "7M;
25'x 4' extent; very bright and large; axis oriented NE-SW; oblique view of SP
GAL; great binocular object; mottling visible at >200x; good supernova
prospect; photo @ HAG-34; 1.75 degrees to SE is GLOB N288."
Steve Coe, observing with a 17.5" f/4.5
at 100X, notes: "Very bright, very large, very, very elongated at 100X.
Many dark lanes with swirls and rifts prominent throughout the galaxy to a
somewhat brighter core. This galaxy displays lots of mottling across its'
surface. It is easy in binoculars or a finderscope. Sentinel 13" 9/10--in
either 10X50 or 11X80, bright, large, much elongated, somewhat brighter middle,
one star on NE end and three stars on southwest end frame the galaxy. 60X with
38mm Giant Erfle-- Very bright, very large, very much elongated 4X1 in PA 45,
much brighter middle, very mottled, beautiful convex lens shape, many dark
markings in arms. 100X--Excellent view, stellar nucleus evident about 20% of the
time, 7 stars involved, two pretty bright oval patches in southwest arm, lots of
dark markings, the most mottling I have ever seen. 150X 14mm UWA--core is
gradually sculptured by dark lanes, oval bright core has tiny stellar nucleus.
220X core has a fascinating pattern of light and dark markings, but no spiral
structure, more like a surrealistic painting.
See also "Visual Astronomy of the Deep
Sky" by Roger N. Clark (1990, Sky Publishing Corporation) page 74.
A supernova erupted in this galaxy in 1940
(14.0p)
Other names: "UA13,E474-29".
Inclination: (face-on, in degrees) 77 Total photoelectric blue mag 8.04
Logarithm of the angular diameter D25 (arcminutes) 2.44 Blue photographic
magnitude 7.72 This galaxy is included in a sample of galaxies with velocity
less than 500km/s with respect to the centroid of the Local Group. [Nearby
Galaxies. Schmidt K.-H., Priebe A., Boller T. (Astron. Nachr. 314, 371 (1993))]
The ESO/Uppsala Survey of the ESO(B) Atlas
lists the magnitude as 8.04. The RNGC (Sulentic and Tifft 1973) notes that this
is a 7.5 mag galaxy. Their coded description reads EL,BM,HISB,KNPCHYSTR.
10x50: very large, bright.
No prominent central brightening. Could have central bulge (?) Between 2 stars -
one could be a pair of stars (?) Elongated in direction of line between 2 stars.
Visible without averted vision (suburban skies, sky ashen grey with very little
contrast.) [Danie Cronje]
11x80: Very elongated
galaxy, wedged between stars. Brightest part is about 11 arcmin across, which is
off-centre in a longer glow 22 arcmin long, mostly extended to the north-east;
it doesn't grow much to the south-west of the two small stars. (exurban skies,
seeing 7, transparency 7, sky darkness 6, lim.mag. at south pole 6.0 (naked
eye)) [AS]
10-inch f/5 Newtonian: At
30x, a stunning object. A very long, unevenly bright ray of light lying in a
field of large and small stars. The galaxy is closely surrounded by several
stars, and it appears to be jammed in between them. The most noticeable of these
stars is a bright, very wide pair, lying on the south-east side of the galaxy.
Because of its uneven brightness, it appears to point to the north-east; from
the start of the galaxy is the south-west, it extends and gradually brightens
towards the north-east, reaching an area of maximum brightness, which very
abruptly and most sharply fades away unevenly further north-east. A bright star
in involved at the north-eastern faded end of the galaxy, and two other small
stars are seen on its surface in the brightest region. (suburban skies) [AS]
12-inch Meade Newtonian:A
showpiece galaxy, bright and almost edge-on. Large elongated with dark knots
spread all over in uneven brightness. A little brighter to the middle with two
bright stars to the south in a busy starfield underline this galaxy beautifully.
About 30 arc minutes in size. (Super 40mm eyepiece, fov 53') (suburban skies) [MS] |