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Cleopatra's Eye (NGC 1535)
Planetary Nebula
aka NGC 1535, PN G206.4-40.5, PK 206-40.1
RA: 04h14m15.8s, Dec: -12°44'21" (2000) in Eri
Integrated Visual Magnitude: 9.6
Magnitude of central star: 12.2
Distance: 5800 ly
Mean Surface Br. 15.9 Mag/arc-secē

Minimum requirements to detect: Any telescope under suburban skies


NGC 1535 is my all-time favorite planetary nebula.  Although a fine object for small telescopes, it really shines in large aperture instruments.  This is a small very high surface brightness object that takes magnification extremely well.  For the best view use at much magnification as the conditions will permit. 


The field in a six-inch at 50x. North is down and east is right.

In my six-inch, this planetary is obvious at 50x.  It appears very bright.  My best view was at 270x, where it appeared as an elongated disk. The central star was visible.  The image on the right closely resembles the appearance of NGC 1535 in small telescopes.

My first view of NGC 1535 in a large aperture instrument came with the first light of my 18" Dob in October 1999.  At 166X its appearance wasn't that different from the view in my 6-inch.  I logged the following, "Nearly round. Very bright. Fuzzy edges."

I inserted a 2X barlow for another look and I was stunned.  Here is my log from that night and a drawing of what I saw:

"As it came into view I was astonished, like seldom before. "Oh my God", I said out loud to the darkness.  This was no visual observation of a planetary nebula.  It was a photograph!  Very bright, with a non-stellar appearing central "star" with sharp edges.  Some dark surrounding this then a bright, slightly oval ring -- quite distinct.  All this embedded in a slightly oval, sparkling haze."

I dubbed this planetary "Cleopatra's Eye", in reference to the oblong inner ring that surrounds the central star as seen in photographs or large aperture instruments.  But I have not seen this or any other name name widely applied.  This is a wonderful object, and I think it deserves a descriptive name.

There are many objects that look pretty much the same in any telescope.  The Crab nebula is one and M 31 is another.  But small planetary nebulae are different.  They require high magnification to see the faint detail that is present in photographs, and the more light available to be spread out under high magnification the better.  So while a big Dob may not always be worth the extra cost, size and weight, it is objects like NGC 1535 that make them worthwhile. 

Millennium Star Atlas Vol I Chart 306
Sky Atlas 2000 Chart 11
Uranometria 2000 Vol II Chart 268
Herald-Bobroff Astroatlas B-06 C-40