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insidethisissue - The Royal Astronomical Society of Canada

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At the EyepieceRoyal Reflectionsby Guy Mackie, Okanagan Centre (guy.m@home.com)As patriarch of the northern skies,the constellation Cepheus wearsits reflection nebulae with asubtlety reminiscent of the “EmperorWho Wore No Clothes.” When I decidedto observe all the diffuse nebulae inCepheus that are listed in Burnham’sCelestial Handbook, I was unaware of theambitious nature of the observing challengeI had set for myself. Vast sweeps of faintcloud and small but bright nebulae withtantalizing hints of structure combinedto make an excellent exercise for developingobserving skills. Stellar ejection nebulaecontain elements of both emitted andreflected light, and I was pleased to find(for the sake of this article’s title) that allof the nebulae in Cepheus listed byBurnham’s contained enough reflectedlight to be visible without using any lightfilters.The first target for my 12.5-inchDobsonian telescope is situated on thefront step of the house-shaped Cepheus.Just a few steps southwest of theconspicuous yard-light “Garnet Star” MuCephei is a cluster and an extremely largediffuse nebula with the combineddesignation of IC 1396. Using a low powerof 63×, the centre of the cluster is markedby the close triple system of Struve 2816,containing a bright yellow star with twodimmer white/blue companions. Thisdistinctive triple sparkles, along withseveral dozen other members of themoderately rich cluster IC 1396, to nearlyfill the entire low power field against adark background encircled by a faintfringe of nebulosity. A slight nudge of thescope off of the cluster in any directionwill reveal a faint murky cloud that, likethe Rosette Nebula, is detected more bythe reduced stellar population than bythe presence of nebulosity. This very dimA 10-degree high finder chart for NGC 7782 showing stars to about 8.5 magnitude(ECU Chart by Dave Lane).nebula requires a dark transparent skyand well-developed dark adaptation beforethe eye can be tuned to truly appreciatethis elusive shade of pale. I found that aUHC filter did offer a slight enhancement;however, while exploring the full extentof this sprawling nebula, I came to preferthe unfiltered view as it allowed the fullcontrast with the rich star fields in thisarea, which brushes the nearby MilkyWay.On a night of excellent seeing, whensweeping the area southwest of BetaCephei with medium/low power, I usedaverted vision to notice NGC 7023 as asmall, moderately bright cloud surroundinga light, straw-coloured 7 th magnitude star.It soon became apparent that the starand its associated cloud were themselvesset within a large faint circular haze.Increasing the magnification to 158×reveals structure in the cloud similar toa very faint Orion nebula as the centralstar is muted by a glowing arc, extendingin a north to south direction, with longtendrils sweeping off the ends. An extendedobservation period using averted visionenhances the bright region north of thecentral star and reveals dark lanes andbays. The entire 0.4-degree field is stronglyaffected by the dim haze of theencompassing nebula, which a move tothe surrounding rich dark star field revealsto best advantage.Using the 1/2 degree distance betweenM52 and NGC 7635 (the Bubble Nebula)as a guide, travel just less than 1 degreeslightly north-of-west from NGC 7635,December/ décembre 2000 JRASC259

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