[AZ-Observing] Re: Thanksgiving Sky

Hi All-

Well, with the long weekend, I decided to go out and take another version
of Epsilon Orionis.  I used my 11cm F/7 APO (second time out in 5 months!)
and the 20Da.  The result was:  Nothing - there is no detectable NGC 1990
nebulosity around eps Ori.  I need to hand carry the file to my computer
at work and with the ASU game at the stadium today, there is no way I'm
getting within 2 miles of that place today.  If anyone is really
interested, I can e-mail the 1.5mb jpeg to you.  Otherwise will post it
tomorrow.  The final image is much superior to the one posted yesterday
and shows nothing besides the IC nebulae and the larger reflection nebula
to the west and very slightly south - does anyone know what it is?  It
shows faintly in the link below.

So the only explanation of why it is in the Pronto image below is a
reflection of some sort that is field-position dependent.  I only borrowed
it for two nights, but did shoot the bright Orion belt stars and also the
cirrus nebulosity around Antares without showing the reflection except on
epsilon Orionis...

-Dean




>>>  http://alice.as.arizona.edu/~ketelsen/epsOriave4cropped.jpg
>
>      Thanks for posting this.  It looks reasonably convincing
> to me, too.  I'll pass this along to Corwin to get his reaction.
> The nebula in Dean's image is about the size of the plotted star-image
> in either Uranometria or the Millenium atlas, whereas the thing
> the 19th Century observers saw was at least 0.4 degrees across---
> the big ameoba shown on various atlases---though d'Arrest (I think,
> perhaps another) observed the field using an occulting bar in the
> eyepiece to block the light of epsilon, and saw nothing.
>
> \Brian
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