Thursday night was predicted to have poor transparency, but fortunately that did not materialize. I started out observing Jupiter during the twilight. At 340x I saw the usual dark barges in the equatorial bands, the one in the southern very long and tapering at the tips like a lenticular galaxy. The GRS was nearly finished with its transit and there was a dark forking barge following it, along with two lighter ovals -- first time I recall seeing such a feature. The barge had swells in them as they extended under the GRS. There was even a barge in the SSTB -- though the whole South Temperate and South Polar region appeared uniform in color. The North Tropical zone was distinct from the Temperate and Polar zones, but these were also a mild uniform color. I'll have to look for separations in these zones in the time remaining this season.
While waiting for the moon and Mars to clear the neighbor's tree, I viewed some doubles in Virgo at 340x; seeing was about Pickering 7:
Rst 3829 / Sh 162: This is a quadruple system with three visible; but I only noted two stars, AB, a widely separated yellow A and orange B, 1 magnitude difference. The Aa Ab system is 0.6 separation, and the BC system has a wide magnitude difference (C is 13.34) which I didn't notice. That's what I get for randomly observing things without research beforehand...
86 Virginis; Stelle Doppie says this is also a quadruple system, and all four should be visible. Again I only noted two, a brighter A and very faint / almost averted vision B widely separated. What I saw was actually the AC pairing, with mag 5.66 A and 11.9 C, 27.3" separation. The AB is 1.2" separation and 5.66 A & 8.47 B. The CD pair is 11.90 and 13.10, 2.4" separation -- I should have noticed a nearby "double double" but did not. I will need to go back...
81 Virginis: I saw a well split close pair of yellow stars about equal magnitude (2.7" 7.79 A & 8.08 B). Unfortunately, this is a triple system with three visible! Missed again! I saw the AB pair but AC is quite widely separated at 137" and a much fainter C at 12.28.
72 Virginis: Bright A and very faint B, widely separated. Luckily this is correct; A 6.14 separated by 29" to 10.74 mag B
STF1775: The losing streak continued: I observed a pretty pairing of a bright orange A and a faint bluish B widely separated. This is probably the AB pair, 27.7" separated and 7.21 mag vs. 10.06. The AC, not noticed, is 38.6" and 14.16 mag.
STF1788: And I closed with a total failure: This is a quintuple system and all 5 are visible. I saw a bright pair of near equal magnitude, both yellow-while color. This is the AB pair. I give you the Stelle Doppie link so you can see how inattentive I was: http://stelledoppie.goaction.it/index2.php?iddoppia=58333
The double session was impromptu, so perhaps I shouldn't be so hard on myself. But, knowing what I can & should see I will retry them the next opportunity.
Mars was now clear of the tree. Seeing had become considerably better, Pickering 8 or 9 -- all the air around me had become still, and the usual loud white noise from the highway was greatly diminished. I pulled out all the stops, as it were: 553x, planetary filter, and apodising screen. It was my best view I've had through my own scope yet, and approaching the very brief look I had through the 36-inch Great Refractor at Lick Observatory about 15 years ago.
Sinus Miridion reached down in a triangular form, with Sinus Sabaeus as a dark barge to the east. The rest of Mare Erythraeum was a dark but somewhat greyish mass covering the rest of the hemisphere; could there have been clouds making the greyish color come out? I noticed two small bright ovals to the west of Margatitifer Sinus but can't account for what it was. Mare Acidalium was a large thick crescent, and I could see the bulge coming out of it to the east, along with some mottling in the brighter plain to the southeast. The southern rim was bright with what could be clouds.
I now understand why observers become so excited during a Mars opposition: with the planet so much closer it offers up a lot more detail. Lin came out for a look and said it looked like the moon -- all the mare visible. I had planned to observe the moon's terminator that night too, but with Mars the way it was I decided to stay on it until bedtime; I can see the moon any month, but not Mars.
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