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A very interesting field
to share with you this week, with a surprise object appearing
just to the right of center. This shot was originally intended
as a field higlighting the star Mu Cephi - the orange star just
below center for use in a popular magazine. As you know, this
star is one of the largest known, with a size larger than the
orbit of Mars. To the bottom we see the beautiful IC1396 with
colors ranging from deep red to pink and magenta. The surprise
here is the ultra faint planetary IRAS21394+5844 - the blue green
object to the right of center. I asked my friend Tom Polakis
to help me identify this object, as it is either not plotted
on any atlas I had, and is actually misidentified on Cartes du
Ciel as a galaxy. He was able to plate solve this image and came
back with this startling identification. Thank you Tom! (And
yes Tom, I now learned how to do this myself!) This object was
only discovered in 1988 with the IRAS infrared satellite and
there are very few images in existence of it by amateurs. Why?
It looks so bright here! I can think of two primary reasons for
this. First - Before 2000, most amateurs used film and especially
color emulsions which are blind to OIII wavelengths because the
two filter layers crossed thier response curves at this point,
and sensitivity was at a minimum. Second, the availability of
inexpensive photographic sized OIII filters was basically non
existent back then. Today, we have highly sensitive digital sensors
as amateurs primary imaging medium, and relatively inexpensive
OIII filters (<$500) to shoot with. In fact - it has been
only in the past few years that these filters have been available
for fast f/2 optical systems. The IDAS NBZ Mark II I used here
is brand new to the scene and works from f/1.8 upwards. The lesson
of this story is that the field is wide open for amateurs with
fast lenses and low f ratio filters to make new discoveries and
maybe you can be the very first to image such obscure objects.
Take heed!
Technical Data: 8 inch
f/2 RASA (IDAS) + 80mm f/5 Stellarvue (RGB) astrographs, ASI2600MC,
2h total integration, Happy Jack, Az
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