NGC 281

NGC 0281 = IC 11 = IC 1590 = Cr 8 = LBN 616 = Sh 2-184 = "Pac-Man Nebula"
00 52 48 +56 37.7
Size 35x30

17.5" (9/28/02): the bright central quadruple (ADS 719 = Burnham 1) contains a 
bright mag 8.6/9.2/9.8 trio at 4" and 9".  At 140x, a fourth fainter companion 
(mag ~10.1) at 1.54" separation is just visible close following the brightest 
member and is cleanly resolved at 324x.

17.5" (10/17/98): spectacular view of this detailed HII region at 100x using an 
OIII filter.  This 15' nebulous complex has a mushroom appearance and is 
separated into three main lobes apparently by dust.  The brightest and largest 
lobe is following a bright triple star embedded near the center (8.6/9.2/9.8 at 
4" and 9").  There appears to be a much fainter detached piece off the south end 
of this lobe.  Preceding the triple star is a section which is noticeably 
elongated and irregular in surface brightness fading to the NW.  The section to 
the north is faintest and separated from the eastern lobe by a curving dark 
lane.  A dark intrusion is visible south of the triple star which appears to be 
due to obscuring dust.

13" (8/24/84): very large, fascinating nebulosity, very irregular, dark gaps 
between sections, five brighter stars involved mag 8.6-12.5.  The brightest star 
is a very close double.

Discovered by Barnard on 26 November 1881 (Sidereal Messenger, Vol 2, p226 and 
AN 108:369, 1884) and described as a large, faint nebula, very diffuse.  
Incorrectly listed as an open cluster in the RNGC (Barnard made no reference to 
a cluster).  IC 1590 is a large, scattered cluster on the W side.  Barnard's IC 
11 was placed 32 tmin W, but Corwin notes that his description "vF, L, triple * 
on np corner" points to N281.

- by Steve Gottlieb

IC 11 = NGC 281.  IC 11 is one of Barnard's discoveries that he sent directly 
to Dreyer; it is not, so far as I know, in any of Barnard's published papers.
Though included in Cederblad's catalogue of bright diffuse nebulae (and thus
plotted in several atlases), it is not on the sky in Barnard's position.  I 
have not found it on the POSS, nor on plate 89 of Barnard's own collection of
comet and Milky Way photographs (Lick Publ. XI; 1913).  

However, the triple star mentioned in the description suggests the identity 
with NGC 281, and makes the RA just 30 minutes of time too small.  I suspect
a simple transcription error on Barnard's part. - Dr. Harold G. Corwin, Jr.
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IC 1590 is a star cluster involved in NGC 281 = IC 11.  Bigourdan says of it, 
"In the region of NGC 281, there is in addition to the nebulosity suspected 
near BD +55 191, a large number of stars forming a very large cluster, without
concentration."  He gives no position in his big tables, but does have one in
his tables of new objects, and in the CR article from which Dreyer took the IC
position.  That position is about 3 arcmin southeast of the center of a group
of stars that Brian Skiff and I independently chose as IC 1590.  I make the
diameters 6 arcmin by 4 arcmin, so am not convinced that this is Bigourdan's
object.  

Without better evidence from Bigourdan's published material, though, there is 
not much point in trying too hard to find this object.  It sits in the middle
of a large region of star formation, and any position we take in the area will 
get us some hot, young stars. - Dr. Harold G. Corwin, Jr.

As with all corrections to the NGC and IC Catalogues, there is a certain margin
for error, even though the evidence supporting the correction may be strong and
compelling. It is with this in mind that we ask the user to use this information
as 'Most Probable', but never to assume the correction is 'Absolute'.  All
published corrections are based on an exhaustive 'paper chase' of the historical
record back to the original discoverer's published notes/papers, and are
therefore based upon the historical accuracy (or inaccuracy) of those particular
notes/papers. In short, Caveat Emptor! - Robert E. Erdmann, Jr.