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DS102203 RECENT OBSERVATIONS
by David Knisely DATE: October 22nd, 2003, 0730 to 0930 hrs UTC. LOCATION: Beatrice, Nebr. 40.284N, 96.735W, 1320 ft. (402m) elevation. INSTRUMENTS: 100mm f/6 Orion SkyView Pro refractor, 20x, 43x, 76x, 122x, 200x, 300x CONDITIONS: Mostly Clear, Temp. 58F, Wind calm. UNAIDED-EYE ZENITH LIMITING MAGNITUDE: 5.8 SEEING (above 45 deg. altitude): 0.8 arc seconds (Antoniadi II). OBJECTS OBSERVED: M31, M32, NGC 205, M33, M45, M42, M43, NGC 2023, NGC 2024, IC434, Sigma Orionis, M78, Rigel, NGC 2237-39-44-46, M36, M37, M38, NGC 1907, M35, NGC 2158, IC 443, NGC 2169, NGC 2174, NGC 2392, M81, M82, NGC 1499, Saturn. OBSERVATIONS: After a few hours working on the computer, I went outside into the backyard to check on the Orionids. The layer of thick cirrus overhead had largely cleared out and the sky was pretty nice, although I only saw a handful of Orionids. After standing out in the dark backyard for a while and seeing Orion high above some trees to the southeast, the scene brought back memories of many years ago, when I stood in that same backyard as a youngster trying out my first little telescope. The trees are much higher today and my "window" on the sky is considerably smaller, but the sky was so nice, that I decided to go back inside to get my 100mm f/6 refractor to do a little "casual" skygazing. Despite being in-town, this was one of the better observing sessions I have had in quite a while, and I now realize why the 4 inch refractors are so popular among amateurs. Getting the scope out of the basement wasn't all that hard, but I did have a few collisions between the tripod legs and the railing of the stairs. Putting things together took little time, although out of an old habit, I tried to keep things quiet as I worked, even though there is nobody in the house but me. My first task in the dark was taking off the 1.25" star diagonal and putting on the 2" Williams diagonal so I could use the full four degrees of field the scope provides (note to self: put *only* one item in your hands at any one time, as otherwise, something important might end up in the grass). After juggling things a bit, the 2 inch diagonal slipped into the focuser and I put my 30mm WideScan III eyepiece in to get as large a field as I could. I looked up and could see 9 Pleiades with my unaided eye so that was to be my first target. The view was simply stunning, with the jewel like stars suspended in the huge field of view. I could even see the faint fan of the Merope nebula, as well as some of the other nebulosity around the brighter 4 "bowl" stars. Indeed, a narrow-band filter seemed to help bring out the nebulosity a bit even though the nebula is a relfection type. A nice reddish star north of the "bowl" of the Pleiades caught my eye (HD 23712), although its spectral class is only K5. From there, it was on to good old M31. The faint skyglow from the city did reduce the contrast a bit, but it was surprising what was visible. The entire galaxy was easily seen, with the faint diffuse arcs of the arms on each end showing up dimly, as well as the marked drop-off in brightness along the northwest side of the core. Both NGC 205 (M110) and M32 were also easily seen, although at ony 20x, NGC 205 looked nearly stellar. Using my Meade 14mm Ultrawide boosted the power to 41x, but still gave me a healthy 1.9 degree true field on the sky, showing the now obvious M32 and the stellar core of M31 itself. Even the first dark lane began to show up a bit. I also took a quick look at M33, and noted it easily as a large oval mottled region with a brighter core. I could see some hints of detail at 41x especially the HII region NGC 604, but the contrast was low and the spiral pattern was not obvious. Moving north, I decided to drop back in field (but not power) to try for the California Nebula NGC 1499 in Perseus. I went back to my 30mm Orion Ultrascopic, as my H-Beta filter is only the 1.25" variety. With that eyepiece and the H-Beta filter, I got about a 2.3 degree field which allowed me to get most of the nebula in. Without the H-Beta, the nebula was only hinted at, but with the filter, it became visible as a large elongated area of faint nebulosity containing two very broad irregular filament-like features, one in the north and another along the south side. With this under my belt, I felt "the call of Orion", and turned the little refractor towards the sword. The views at 20x were very nice with the entire sword and surrounding region easily visible in the 4 degree field of the 30mm WideScan III. With a narrow-band filter, the huge faint arc of nebulosity which extends southward from the main mass was faintly seen, along with the huge east and west "wings" of the nebula. The real surprise came at between 76x and 122x using my 4.9-7.9mm Speers-Waler eyepiece. The dark nebula known as "the Fish's mouth" changed its appearence, becoming almost a huge dark wedge extending well north past M43. It looked a bit like images of the Cone Nebula (NGC 2264), probably due at least in part to the fact that the star diagonal was reversing the view from that I normally get with my Newtonian. There was a tremendous amount of detail visible, and I could have spent hours on this one object alone. Off to the north, I could see the dim nebulous cluster known as "the Running-man Nebula" NGC 1977. The irregular dark lane down the middle which gives the object its name was visible with averted vision but was not as sharp or detailed as it was in my 10 inch. However, in the 100mm f/6, it was still pretty impressive just to see the nebula at all from in-town and with such a modest aperture. From there, a quick trip to the southwest brought the bright double star Rigel into view. It took higher power, but in the violet haze around the primary, the tiny speck of the faint companion was clearly visble. More impressive was the multiple star Sigma Orionis, which has multiple companions in an area which does not require a lot of power. I could glimse the faint "Flame Nebula", NGC 2024 at 30x as two dim irregular areas of brightening, but it took some movement of the scope to bring them out. With the H-Beta filter, I could also see the faint streamer of light IC 434, but could not see the dark inclusion which is the Horsehead, although the nearby oval nebula NGC 2023 was easy. Moving to the northeast, I passed by M78, seeing its small faint fan- like form fairly easily. Wall off to the east, I located the Rosette Nebula which showed its wreath-like form of dim nebulosity surrounding the small oval star cluster NGC 2244 when I used a narrow-band filter. I stopped briefly at the "37 Cluster" NGC 2169 but the star diagonal made it look less like its name than the view in larger "correct-image" telescopes. Going back north, I ran into the nice nebula NGC 2174, which with the UHC filter appears as a round area of haze with irregular boundaries around a magnitude 7.6 star. At 43x, it showed some hints of detail in its interior and looked a bit like a flower seen from the top. Not far away just east of Eta Geminorum, I glimsed the faint arc of the supernova remnant IC 443 using the UHC filter. Far more impressive was nearby M35, which is one of my favorite open star clusters with several strings of fairly bright stars. Next to it was the misty patch of NGC 2158, an open star cluster much farther away. Surprisingly, at 122x, I could see a few of this cluster's brighter stars which is interesting, considering most of them are fainter than 12th magnitude. I moved up into Auriga to check out its open clusters with the wide view of my 100mm f/6 refractor. M37 is one of my favorites, and it didn't disappoint me even at 20x, showing a nice compact mass of stars almost like a poor globular cluster. Next was the coarser but still pretty cluster M36, which stood out quite well even at only 20x. Finally, I looked at the adjacent pair of open clusters M38 and NGC 1907. M38 appears to be roughly wedge-shaped like M11 is, and is quite rich and beautiful. NGC 1907 was small but partially resolved. The pair look a bit like the M35/NGC 2158 duo. I swung back over into Gemini to try for the "Eskimo" Nebula NGC 2392. I had little hope of catching it at 20x, but was surprised again to see its tiny fuzzy star-like form contrasting with the 8th magnitude star which sits right next to it. I kicked the power up to 122x and was surprised again, as the nebula's faint central star, brighter inner shell and ring-like outer shell were all visible, although the shells tended to appear as overlapping features rather than the more separated ones I see in my 10 inch Newtonian. With the scope in Gemini, I just had to try Saturn at high power. Seeing was very good, and the planet took high power well. 122x showed the rings, Cassini's Division, and the moons Titan on one side and Rhea on the other. The small residual color of the 100mm f/6 refractor's simple 2-element achromat did cause some scattered light around the planet, but I could still glimse Tethys and Dione in the glow at 200x. I pushed to 300x, but it was clearly just a little too much for the scope. Still, at 200x, the image was a lot better than I had expected out of a scope that is supposed to only be used at lower powers. The planet itself showed its darker polar "cap" and the main equatorial belt, while the dim Crepe ring also made its appearance inside the inner edge of the B-ring. The Cassini Division was nice and sharp, with the view being one of the better ones I have had of the planet recently. For a final target, I moved the scope over to M81 and M82. Both were nicely shown in the 4 degree field of my 30mm WideScan III eyepiece. 41x showed the dark "bar" in the middle of the fuzzy cigar of M82, while hints of vague diffuse detail were seen on the north and south sides of M81. All in all, it had been a wonderful backyard experience, so I may try this little "small aperture" experiment again soon. Clear skies to you. -- David W. Knisely Prairie Astronomy Club: http://www.prairieastronomyclub.org Hyde Memorial Observatory: http://www.hydeobservatory.info/ ********************************************** * Attend the 11th Annual NEBRASKA STAR PARTY * * July 18-23, 2004, Merritt Reservoir * * http://www.NebraskaStarParty.org * ********************************************** |
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Thanks for sharing with that delightful report, David. Being stuck
working at the computer late tonight -- and with hazy skies due to smoke from wildfires anyway -- I enjoyed your backyard night with old friends vicariously. "Casual" observing with small apertures and wide fields always makes me feel a bit more in touch with the sky than big scopes do. And there's a nice bit of nostalgia as well, as with your own recollection of long-ago nights from the same location under the same sky. Mike Simmons |
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David Knisely wrote:
DS102203 RECENT OBSERVATIONS by David Knisely DATE: October 22nd, 2003, 0730 to 0930 hrs UTC. LOCATION: Beatrice, Nebr. 40.284N, 96.735W, 1320 ft. (402m) elevation. INSTRUMENTS: 100mm f/6 Orion SkyView Pro refractor, 20x, 43x, 76x, 122x, 200x, 300x CONDITIONS: Mostly Clear, Temp. 58F, Wind calm. UNAIDED-EYE ZENITH LIMITING MAGNITUDE: 5.8 SEEING (above 45 deg. altitude): 0.8 arc seconds (Antoniadi II). OBJECTS OBSERVED: M31, M32, NGC 205, M33, M45, M42, M43, NGC 2023, NGC 2024, IC434, Sigma Orionis, M78, Rigel, NGC 2237-39-44-46, M36, M37, M38, NGC 1907, M35, NGC 2158, IC 443, NGC 2169, NGC 2174, NGC 2392, M81, M82, NGC 1499, Saturn. OBSERVATIONS: [snip] Nice report, David. Many of the objects I will be observing myself around December, so it's nice to have something to compare against. Thanks for sharing this. -- David W. Knisely [snip] -- Ioannis http://users.forthnet.gr/ath/jgal/ ___________________________________________ Eventually, _everything_ is understandable. |
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