took this image of NGC 1535 with iTelescope
T32. It is a color composite made
from 2x3min exposures in OIII and H-alpha filters. The OIII was
mapped to blue and the H-alpha to red. Green was synthesized as a
combination of the two. The OIII line is the stronger, thus the
The field in a six-inch at 50x. North is down and east is right.
|Visually, 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, it is
important to use as much
magnification as the conditions will permit. Make sure it is
high in the sky. If the seeing is poor, come back on
another night and try again. It really is worth getting a
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
My first view of NGC
1535 in a large- aperture instrument came with the first light of my
18" Dob in October 1999. Its appearance at 166X 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 (left):
"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."
This is a wonderful object that should have a
memorable and descriptive name. I dubbed it "Cleopatra's Eye", in reference to the oblong inner ring
that surrounds the central star. It is gratifying that as a
result of my original post over a decade ago, this name has found
some acceptance in the visual observing community.
Your Own Observation
more columns are available, but we had to squeeze things to fit
our space here.
Nightly Planner is set up above for December 18,
Chiefland Astronomy Village, and a 10-inch LX200. Cleopatra's
Eye is selected. The graphic at the top shows the darkness of the
sky during the night. The red dashed line is the altitude of Cleopatra's
Eye. The teal line is the altitude of the moon, which you can see
rises at about 23:00 (11 PM). We can readily see that our best view
will be from about 8:00 PM to 11:00 PM, when our object is highest in
a dark sky, and this is reflected in the times listed in the Begin,
Optimum, and End columns. This marks the first night
that gives if a really good view this month.
Other software may do
something similar, but they only make generic claims for your
telescope, rather than specific calculations for an actual night
under actual observing conditions, including the altitude and
phase of the moon and level of light pollution at Chiefland. On
another night, SkyTools may say that the object is difficult to
see in the eyepiece rather than obvious.
we right-click on our object we have options: to see everything
SkyTools knows about it (right), to view in it the Atlas,
view/print a finder chart, slew your telescope, create/view log
entries, download a DSS image, etc. The time is automatically
selected to be the optimum time to view.
below to see a full size finder chart that was made by
right-clicking on the object in the planner.
finder chart is for an 8-inch Dob. The
left side shows the naked-eye sky with Rigel QuikFinder
circles at the location of the object. On the right is the view in
a wide field eyepiece. The orientation and magnitude limits are
properly calculated for the time and location, including light
pollution, twilight, and moonlight. As a result, it is a simple
matter to find this tiny planetary. Once centered, insert a
higher-power eyepiece. A version of the same chart
can be printed and taken into the field.
Greg Crinklaw — Developer of
3, because the astronomy matters.
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