[AZ-Observing] Putting NGC 1990 to bed (was Thanksgiving Sky)

All-
Below is the link to the older image (70mm Pronto) with the hint of cirrus
nebulosity around epsilon Orionis (center belt star of Orion).  I reshot
it friday night with 110mm WO APO.  It can be found at:

http://alice.as.arizona.edu/~ketelsen/epsORI27mexpRCS.jpg

or with a dithered view AND another 13 minutes of exposure:

http://alice.as.arizona.edu/~ketelsen/epsORI40mexpRCS.jpg

It might be stretched a little much, but in the original Pronto images, it
could be seen in the frames before stretching - the cirrus cannot be
detected at all in friday's data.

And while waiting for Orion to rise, I shot the Pleides too:

http://alice.as.arizona.edu/~ketelsen/M45ave6RSM.jpg

for a nearly full-frame view, or for a closeup showing an edge on galaxy
visible thru the cluster on the right:

http://alice.as.arizona.edu/~ketelsen/M45ave6SCRSM.jpg

I thought I could see the brighter Merope nebula (very close to the star
made famous with the Hubble shot), but it is blown out in the above
stretches, and I would just as soon not show an imaginary feature twice in
the same long weekend!

-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
> --
> See message header for info on list archives or unsubscribing, and please
> send personal replies to the author, not the list.
>
>

--
See message header for info on list archives or unsubscribing, and please 
send personal replies to the author, not the list.

Other related posts: