Viewing Notes
January 12-13, 2001
Empire Ranch
(W110º 37' 48", N31º 47' 29")
Obsession 20 inch f/5 reflectorThe Eskimo Nebula at 1,700x!
The TAAA held its club star party at Empire Ranch on Saturday evening. This time the turnout was great. About 20 - 25 telescopes and about 40 people.
The guy next to me had The Eskimo Nebula in his scope (13 inch Dob) and wanted to see how his image compared to the 20 inch. He was at about 200x so I popped in the 12mm Nagler for 246x. Surprisingly, the detail in his scope was just as good as in the Obsession, the only real difference being the brightness. The central star hung in real well at this magnification. A few minutes later he told me he was viewing it at 600x and that it still looked pretty good. I used the 9mm Nagler with the 2x Big Barlow to bump the magnification to 655x. The inner structure was even more evident and the central star still was very apparent. Another friend asked if I wanted to try using his 4.7mm Meade Ultrawide, 2x barlowed, for an effective magnification of 1,090x. Amazingly, the detail was still present as before, but with a larger image. We were all impressed that this object was taking this magnification so well. Another friend asked if I wanted to try his 3mm Radian, 2x barlowed, for an effective magnification of 1,708x. And the image held up very, very nicely. Well beyond the theoretical useful magnification limit of 50x per inch of aperture. The central star was still not blown out to mushiness and the inner structure was still very apparent.
Another aspect almost lost in this magnification frenzy was that the scope was actually tracking at this magnification. Tom Osypowski's platform was performing flawlessly, using only an "eyeball" alignment to Polaris. The magnification was too great for hand-guiding, and it took a bit of maneuvering to get the image in the center of the field. I left the hand control for the dual axis platform at home, otherwise centering would have been a breeze. Even at 1,700x the image stayed in the field of view for enough time to allow 5 of us to take turns climbing up the ladder, google, and climb back down. I think this had to be at least 3 minutes of tracking, perhaps more.
M46 with the planetary nebula NGC 2438. The cluster is really too large to be viewed at 95x, but that's the smallest magnification I had available. The planetary was nice and bright, even without the use of an O-III filter.
M57, no central star visible this evening. The seeing and it's location near the sky glow of Tucson wouldn't allow for this. Still, many members got to see the oblong structure for the first time.
The Veil Nebula, east (NGC 6992) and west (NGC 6960) components viewed with an O-III filter. The east component got the most oohs and aahs as there is much more of this to view than the segment of NGC 6960. I showed the viewers how to move the scope around to follow the entirety of this component. It really is huge.
The Crescent Nebula (NGC 6888) viewed with an O-III filter. In the neighborhood of The Veil Nebula and a very nice object to view. The O-III brings out more detail than when viewing unfiltered.
Saturn was fantastic and a fellow observer reported he was viewing at 400x in his 10". I bumped the magnification up to 327x (Nagler 9mm) and found the planet to be stable for extended periods of time. I added a 2x barlow to increase the magnification to 655x. The Cassini division was holding up very nicely and there were periods were I was able to see Enke's minimum. The upper left of the planet was just beginning to cast a shadow on the rings and this intensified the 3D appearance of the orb.
Jupiter was good, with Io appearing from behind the disc. Seeing wouldn't really allow for much detail in the equatorial bands but some mottling was seen, along with a white inclusion in the Southern Equatorial Belt (SEB).
The Flame Nebula, without an O-III filter showed a lot of detail. I was in the area, attempting to show another member where the Horsehead Nebula was at, even though we had no chance to observe this without an H-beta filter.
M33. The H-III regions were apparent, but other detail in the spiral arms was not as noticeable this evening.
M31, A couple of volunteers from The Flandrau Science Center were in attendance and I wanted to show them M31 though the 20". I had visited their observatory and looked through the 16" cassegrain, commenting on how dim the galaxy seemed. In all fairness, the Flandrau Observatory is on the University of Arizona campus, near downtown Tucson, and suffers from urban light pollution. Both were impressed at how much more detail could be seen, commenting that M110 at higher magnification (I think 245x, 12mm Nagler) looked similar to what M31 looks like through their 16" scope. With 95x being the lowest magnification I could achieve I was barely able to get M31, M32, and M110 in the same field. Obviously, most of M31 wasn't in the field.
NGC 891, a nice edge-on galaxy in Andromeda. The central dust lane was clearly visible, but the galaxy itself was not as bright as I've seen in the past. This could have been a result of its relatively low (~30º) position in the sky.
NGC 253, The Sculptor Galaxy. Again, I spent the most amount of time viewing this magnificent galaxy. The 31mm (95x) does a very good job of framing the entire galaxy. The 22mm Panoptic (134x) gives a little too much magnification to fit the entire galaxy into the field. This galaxy was high in the Southern horizon and took magnification very well. The internal mottling/dust lanes were best viewed at 245x (12mm Nagler).
NGC 3077, I found this galaxy while hunting for M81 and M82. I had first thought it was M81 and realized I was wrong because I couldn't find M82 nearby. NCG 3077 looks similar in structure to M81, a spiral galaxy, but is smaller much fainter.
M81 was in the sky getting close to the light dome of Tucson, however hints of the spiral arms could be detected.
M82, The Cigar Galaxy, was best viewed using the 12mm Nagler (245x). The view at 327x was also good, but some of the contrast was lost.
The Moon rose about 3:30 (1030 UT) but didn't interfere with the views of Jupiter and Saturn. We viewed for about another 45 minutes and then got a short nap before sunrise.