Original image courtesy STScI Hubble Space Telescope. Digitally reprocessed to mimic color through O-III filter.
Viewing Notes
June 28, 2003
Las Cienegas (Empire Ranch)
Obsession 25" f/5 Dobsonian Reflector
The desert Southwest's monsoon season is just around the corner which means that observing opportunities will become rare here in south eastern Arizona for the next couple of months. Accordingly, I jumped at the opportunity for an all night observing session with some other members of TAAA. I arrived a bit late because I stopped along the way to help a poor guy who had brought his family out to the star party, only to have his vehicle break down along the way. Not being mechanically inclined, I offered the only thing I really had to offer which was the use of my cell phone. Satisfied that he was taken care of (I left my phone with him and made arrangements to pick it up the following day) I went on to the observing site. I finally got everything set up by about 9:30 and gave a private astronomy tour to a family whose dad was awed by the 25" Obsession. Seeing conditions were estimated at: Visual magnitude = approx. 5.5, Seeing = approx. 6/10, Transparency = approx. 6/10 (though there were some thin clouds in the south, moving east to west)
I first showed them M51, The Whirlpool Galaxy. I was using the 31mm Nagler and, while not the best view I've seen through the 25", the spiral structure of NGC 5194 was readily seen with direct vision. Their little boy, Patrick (I think), said it looked like an octopus --- confirmation that he was seeing the spiral arms.
The father had asked too see M13, The Hercules Cluster to compare what he had seen in a 5" refractor, 8" SCT, and 12" SCT. The view through the 25" really impressed them, with the little boy yelling out a "Wow!" as he looked through the eyepiece. I was glad his mother gave in and let him climb the ladder: M13 was almost at zenith so I climbed up the back end of the ladder to hold on to the boy while he looked through the eyepiece. His mother even climbed up for a view and commented that this view was so much better than the other telescopes.
Before they left I moved the scope over to M57, The Ring Nebula, and used the 12mm Nagler. Again, the expected oohs and aahs. They thanked me and politely left the viewing area, driving by very slowly to keep the dust down and with their lights off. After they left I hooked up the Argo Navis and did the two star alignment. I went back to M57 to see if I could coax out the central star. The central star was visible only with averted vision. I put in the 9mm Nagler and held the central star for longer periods. The view through the 5mm Nagler showed some structural brightening in the top left hand corner - something I hadn't seen before.
Since I was in the area and the viewing conditions were favorable, I decided to test the optics to see if I could split Epsilon Lyrae. I first tried with the 12mm Nagler and was able to split each pair. This was only intermittent and associated with the seeing. Each pair was more easily split as I increased the magnification using the 9mm and then 5mm Naglers. Satisfied with the performance of the optics, I moved over to the Veil Nebula and was totally blown away with the view through the 17mm Nagler and the O-III filter. The structural detail was so great that I had to call over a couple of other guys to confirm what I was seeing. One guy commented that the area near the double star WDS 14259 looked like a jet contrail. The image below is very close to what this looked like at the eyepiece. Honestly! This was, by far, the best view of the evening.
Original image courtesy
STScI Hubble Space Telescope.
Digitally reprocessed to mimic color through O-III filter.
The summer Milky Way was rising nicely and the high, thin clouds were nowhere to be seen. The mottling of the Milky Way was readily apparent with the bifurcation extending way down in to Scorpius. Since I had the O-III still in the scope, I decided to cruise an old favorite: Nebulae Row. The first object to view is the M16, the Eagle Nebula. The dust clouds were more visible with the O-III filter than without, and the eagle formation was visible, more so with indirect vision. The next nebula was M17, The Swan Nebula. The structural detail was stunning, especially at higher magnification (12mm with Paracorr = 300x). M20, the Trifid Nebula was the next nebula to view in this area. I removed the O-III to see if I could make out any color and found that, while not really pink, I could distinguish each lobe based on a marked color difference. I actually prefer the non-O-III filter view of this object. The last nebula in Nebulae Row is M8, the Lagoon Nebula. This object is best viewed with a wide field eyepiece because it covers such a vast area. I used the 31mm Nagler which is the lowest magnification I can go (116x with the Paracorr, 101x without). I am always impressed with just how large this object really is. I think it is actually larger than the Orion Nebula (M42). Higher magnification (300x) and Nagler 9mm (400x) helped to bring out some of the dust cloud detail, especially around the "neck" region.
Testing the Argo Navis, I moved over to M4 and M80, both globular clusters in Scorpius. M80 has a very compact core, while M4 is larger and more diffuse. Both objects were affected by poor some seeing in the southern horizon.
By this time Mars had climbed to about 25 degrees in the southeast sky so I decided to give it a try, not expecting much because of its location. The view wasn't as bad as I had anticipated with the south polar cap dominating the view. It was clear that Mars was not full phase, and looked to be about 90%. There was a dark demarcation between the south polar cap and the rest of the planet's surface. Mare Erythraeum was evident at times, with Chryse indirectly visible as it formed a break in the darker mare. The image was o.k. (not great) for about an hour and then the seeing went south around 0900 UT 29 June 2003. Even though Mars was higher in the sky, the plant image was roiling. I did take another peak around 1105 UT 29 June 2003 and the seeing did settle down to what it was when I first viewed the planet earlier in the evening.
I decided to continue with my list of the Caldwell objects and managed to view the following: C55, The Saturn Nebula. Nice view of the "wings" using the 12mm, 9mm, & 5mm Naglers. The central star was prominent in all eyepieces. C57, Barnard's Galaxy. Viewed with the 31mm Nagler. Very diffuse object and larger than I expected. I did not try any higher power eyepieces. C27, The Crescent Nebula. I actually viewed this after I looked through Bob Zawada's 15" Obsession. He had asked me to help identify this in his scope and I moved the 25" over to this object for comparison. I first used the 17mm Nagler which framed the nebula very nicely, but switched to the 22mm Panoptic which was probably the best combination for this object in the 25". Next up was C62 (NGC 247), a spiral galaxy in Cetus, reminding me a bit of NGC 253, The Sculptor Galaxy (C65), which is only 4 1/2 degrees away. NGC 253 galaxy is huge and shows a lot of structural detail. Unfortunately, this evening's view wasn't particularly spectacular because it was positioned above the sky glow from Sierra Vista, AZ. The next Caldwell object for the evening was C63, The Helix Nebula. This object reminds me of a larger, more faint version of M57. The central star was visible using the 12mm Nagler. The best image was with the 17mm Nagler and I also looked at this with the 31mm Nalgler. C56, (NGC 246) a planetary nebula in Cetus, was a great object to see. Using an O-III filter and switching between the 22mm Panoptic and the 17mm Nagler, this object looks like a bubble, with one edge (lower right) looking brighter than the rest of the margin. This difference in brightness could be seen with and without the O-III filter. I took a break from the Caldwell search because I saw that Pegasus was high in the sky, meaning the Andromeda galaxy (M31) was visible. The dust lane between the spiral arms was much more pronounced than what I remember seeing with the 20". The satellite galaxies M32 and M110 were large and bright, with M110 looking like a miniature M31. M33, The Pinwheel Galaxy was huge and many H2 regions were visible. The transparency of the skies was beginning to fade with the onset of dawn around the corner. Spiral arms were seen, but they really did not jump out like what I remember seeing using the 20" at a dark site south of Flagstaff, AZ. Since I was in this area of the sky I cruised over to NGC 891, a very nice edge-on galaxy in Andromeda. Again, the transparency really cut into the quality of the view because this is a relatively low surface brightness object to begin with. Still, the central dust lane was visible throughout the entire galaxy. Realizing that my viewing session was about to end I tried for a couple more Caldwell objects. C43 (NGC 7814) is another edge-on galaxy that looks a bit like the Sombrero Galaxy (M104), except the dust lane evenly splits the galaxy and is much more difficult to see. I looked at this with the 17mm Nagler (best view) and the 22mm Panoptic. Nearby is C44 (NGC 7479), a nice barred spiral. The central bar was easily seen with the 22mm Panoptic, but the trailing arms were only visible with averted vision because dawn was here.
Venus was already low on the eastern horizon which meant that the Sun would be up very soon. The remaining TAAA members left as I was packing up (I could hear them packing up as I was viewing the last few objects) and I was all packed up and on the road by 5 AM local (1200 UT). I will always remember the fantastic view of the Veil Nebula on this viewing session, which was pretty darn good.
