Special Observing Report
SCAC Bonny Dune Star Party: 2/09/02

Spectacular blue skies all day Saturday promised to continue throughout the evening. Arrived at the SCAC deepsky observing site around 6:00pm. Fellow members Dwight and Ralf (Meade LX-200's mounted 200 and 250mms respectively) were in process of setting up. I made it a threesome. Dean (200mm Meade SCT), Jack (10 inch Orion Dob), Leon (10 inch Coulter Dob) and Mark (TV-85) joined us as the night progressed. Our "Merry Band" of Night Sky adventurers was assembled. And the promise of the day held true to form...

Once 150mm Argo was setup, Jupiter, Saturn, and Mars were easily located in the darkening sky. Sky stability was none too good at the time (maybe 6/10). But there was something of "deep" about the atmosphere. The wait had begun and the planets beckoned...

Due to small apparent size and sub-marginal stability, Mars offered little visual satisfaction. It's minute and bubbly gibbous disk flared with atmospheric turbulence. Club president Dwight felt confident that stability would improve as the evening progressed. - I had no reason to doubt his optimism since I'd seen this behavior before at the same locale.

Talk turned to the club's binocular 14 inch scope (built by Dwight and SCAC club secretary Chris). I mused on the virtues of some kind of (more or less permanent) observatory installation for the scope. The idea was well met - but without an "evangelist" (not me, dudes, not me) it is unlikely to happen any time soon. Dwight mentioned his hope of bringing this "super guaged double-barrel photon collector" to a Bonny Dune star party. Any prospect of viewing through the "Double 14" is enough to keep me coming. (As though the expansive and fine skies of the 2500 foot Bonny Dune site are not enough motivation...)

Despite the abscence of the "Bino-Rhino", we still had a decent collection of equipment arrayed about us. Nice (more or less) straight row of scopes ranging from three and change, to 10 inches in aperture. One APO, one Mak, two Newts, and three SCTs. Armed for "Great Bear". Why not look through them all?

As mentioned, "The Incredible Shrinking Planet" wasn't showing much of itself. It was placed however, well up in the sky. This prompted a collective marvel at how game the "fourth rock from the Sun" was in the "run around the Sun". No wonder it takes two whole years for Mars to complete a cycle of the ecliptic!

By skydark, we had no trouble turning up a well-ingressed GRS in Jupe's cloudtops. The "socket" was well defined. As it transited the central meridian, the GRS's queue of trailing white ovals became apparent. Above them a large triangular projection could be seen descending from the SPR. It's apex aimed right at the GRS itself. Further ingressed from the projection - but well past the GRS - a segment of the STB could be seen. Between GRS and STB a gap appeared - but the hoped for white ovals ascribed to this region could not be distinguished.

Across the divide of the Equatorial Belt, the NEB showed evidence of numerous festoons breaking in toward a broken, EB. As such, the NEB showed an unusual degree of edge irregularity - especially trailing the GRS.

The NTB was also very present and well-delineated. To the north several faint belts could be seen breaking across the NPR. But I was particularly anxious to make out those white ovals proceeding the GRS. And this particular level of fine detail was just not to be...

As I describe this I am mindful that Argo was giving the best view of Jupiter of the various scopes throughout the evening. The 10 inch Dobs were too short focused and the three SCTs showed image traversal shifts (a sign of miscollimation). Recognizing this Dwight brought out the allen key and tweaked the SCT's secondary. Dean was anxious to have his tweaked as well. So while had a peak of the Great Nebulae through Jack's 10 inch Orion Dob, Dean's 200mm was touched up as well. As a "collimation-nut" I took great pleasure in hearing Dean's rapturous exclamations as to the improvement in star images once the procedure was finished.

Dean got busy coupling a 35mm camera to the SCT's visual back. Meanwhile Dwight and I viewed the Gas Giants. Dean took several exposures of both planets during this period. (Dean hopes to give me the prints next time we meet for scanning and post right here on Astro.Geekjoy.)

I had done a sketch of M78 and neighboring NGC bright nebula earlier in the week from Backyard, Boulder Creek. Sky conditions were less than favorable. Dropped by that same region again, and found that everything seen with averted vision under 4.6 transparency was obvious at 5.5. M78, large and expansive, showed an extensive brightness gradient. Smaller NGC2701 could be easily detected near its illuminating source.

While I pursued planetary nebula NGC2022 (near Lambda Orionis), everyone else was making a run on the Horsehead Nebulae south of Alnitak. Although all the scopes I looked through showed some of the necessary reflecting nebulosity - none revealed the signature horse head obscuration. All pale grey and small - it could be found easily turned up at 50x. Argo's view at 120x gave a strong hint of an annularity. Argo continues to impress me with it's ability to resolve and display small planetaries.

About 11pm a pair of visitors dropped by. Thereafter a good deal of time was spent 150mm Argo and Dwight's 200mm SCT. A Galilean approached the limb (Io?) and we followed it's progress inbound along the northern edge of the SEB. After maybe 30 minutes we lost the satellite: It's tiny globe was no longer perceptible against the SEBs. Dwight thought he could continue to follow it as a "small white oval" right on the border of the SEBn. By this time I had resumed my deepsky advenetures and hoped to capture shadow transit before breaking down for the night.

Seeing stability peaked out while following the satellite's ingressing disk. As the GRS approached egression, a pair of dark barges could be seen straddling the central meridian within the NEB. A single hemispherically-shaped white oval formed a white crescent between them. Meanwhile, I followed the GRS's train of white ovals. As an encouragement to beginning Jupiterphiles, this level of detail was beyond me last year when I first began following the planet closely...

Due to the fine combination of transparency and stability, the night conduced to a fine mix of planetary and deepsky exploration. NGC2024 - The Flame Nebula - near Alnitak gave very fine views through all scopes. Two lobes were obvious. filamentary structure copuld be seen through Dwight's 8 inch. The general impression that of ten fingers projecting off two partially cupped hands.

The Great Nebula in Orion was its usual spectacular self. Trap E discernable, but F proved somewhat illusive (in all scopes). The sky was generally quite dark - except early on when that darn Zodiacal Light "yucked up" the sky to the southwest. By quitting time (1am) counted three stars direct and unaided in the bowl of Ursa Major. Suspect we were down in the ZULM 5.8 range...

Speaking of that Zodiacal Light - tracked down galaxies M74, 77 right in the thick of it. 74 seemed impossible until I swung further east of Eta Piscium than expected. Through 150mm Argo, a large, vague glow with slight central concentration could be seen. The view through the 8 inch was similar. Interestingly, the 8 incher's view of M77 was visibly superior to that of the 150. Sky transparency less than 5.0ULM at the time...

Visited with the M81/82 and NGC3077 Galaxy Troika. Bode's Galaxies are always a treat - obvious and well defined with enough structure to encourage long "hang time" at the eyepiece. The neighboring NGC is fast becoming a favorite. It's position at the foot of a bright triangle of 8th magnitude stars makes for easy identification. There's another NGC galaxy out there and the plan is to make a concerted effort to "grok" the whole region as Ursa Major takes precedence over Cassiopeia in the night sky.

Dean tracked down the Owl nebula through his 8 inch SCT. With nebula filter in place, could just catch the brighter of the two "owls eyes" - something which can be occasionally glimpsed through 150mm Argo (under the very best conditions)...

About this time the Unicorn sprang into "the sky's dark zone" south-southwest. Here all light pollution is in abeyance and the well-behaved laminar air flow off the Pacific Ocean gives remarkably solid views - even far south. Soon it was "all scopes on the Rosette Nebula". Only Mark's 85mm APO, and Leon's short-focus 10 inch Dob (at 30x) could fit the whole one plus degree of this large "lobular" nebulosity in the field. We payed especial attention to the dearth of brightening in the immediate region of the six bright stars that dominate the nebula's central open cluster. This simplified detection of the largest brightest lobe of luminescence southwest of the cluster - with or without a nebula filter.

Mark headed off into the Winter Milky Way to turn up a few large open clusters. One, CR140 I'd found earlier in the week through the Pup. Mark's efforts also "netted" the Duck Emission Nebula (NGC2359) - northeast of Sirius. The view was so nice through the three and change APO, that I just had to take it in through Argo as well. Through both scopes two widely spaced regions of condensed luminosity could easily be made out.

After this "pause for reflection", I resumed "Galaxy-Quest". The Leo Trio were easily located and gave a fine view - especially the large, haunting NGC3628 edge-on. Mark mentioned that the Black Eye Galaxy (M64) could reveal something of its dark lane through a six inch. Sure enough, one face (the southern) appeared better delineated than the other. Inspected the M51 / NGC5195 pair. On eye movement, we caught a definite counterclockwise spiral to the larger, brighter Messier. On a lark, boosted magnification to about 200x. The Whirlpool Galaxy became a large faint study in splotches of light and dark filling half the field of view. - Simply must try this again!

Earlier in the evening had a look at winter's only globular cluster - M79. Able to resolve about a dozen outliers with averted vision. Some three hours later, took a look at a still ascending M3 - not the best view had of this marvelous springtime cluster - but still, hundreds of outliers just within the "outer limits" of perception.

This particular evening of star party revelry and "devil may care" stargazing ended with a view of the Galilean's shadow traipsing across the planet's huge, brilliant girth.

From our own solar system to distant "whirling island universes", our merry band of intrepid explorers had covered a lot of "celestial ground". And there's plenty more where that came from.


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