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Old 06-09-2012, 09:00 AM   #13
Urbane Guerrilla
Person who doesn't update the user title
 
Join Date: Jul 2002
Location: Southern California
Posts: 6,674
The crosspost.

Last one for over a hundred years! Now from today, Venus appears as the Morning Star, after its stint as the Evening Star and its spectacular dance from earlier in the year with Jupiter, whooping down from South to West as our Earth lapped it.

Wow, am I ever glad I made the minimal effort to observe it! Minimal effort read as "drive to Moorpark College and find the VCAS set up by the campus observatory," even if the VCAS website said nothing about whether they'd be observing or not. I figured they wouldn't miss something like this -- well, they didn't. If they had, Griffith Observatory would have been the next stop!

Observing conditions were excellent, and the "seeing" was steady. I got to eyeball our Sun through solar filters over scopes, many of them, of a lot of different apertures. Eclipse glasses were much in use, the wife and I have two pair from an old issue of Astronomy magazine. A transit of Venus is just barely a naked-eye object for me -- at the very limit. It went in and out of visibility, and if I didn't know it was there I'd've easily missed it. Other observers with keener eyes could pick it up readily. But there were moments when the black dot there could be picked up by my aging Mk I eyeball. I needed a telescope to teach me it was there for sure. I tried projecting a sun image through a pair of 7x50 binoculars -- handheld is not good enough. Pinhole camera setup, same thing; lacked magnification.

They warn against catastrophic failures or other accident with solar filters placed over the objective of any scope, from things like heat buildup cracking filter glass. There were no failures. All the filters were plastic film. Some cautious folks -- rightly so -- taped their filters in place, and good for them.

I got to observe the sun disc through one fellow's solar scope with a hydrogen-alpha filter to it -- LED red, and you could pick out the sinuous lighter forms of solar prominences. Thanks, Hal, that was way cool and you're a gent. And thanks, Terence, for offering to email me your multiexposure pics of the event once you have the images shopped all together.

Of sunspots, there were a few. Less than a dozen. Couple of biggies a bit toward the Sun's southern limb. Venus passed near to a curving string of smaller sunspots that looked like a reversed image of the Hawaiian Islands. You can't confuse Venus' solid disc with the splodgy shapes of sunspots, at all, and it was bigger than any of the spots. I did not notice any solar prominence closely associated with a sunspot, not by eye anyway.

When the sun got low, everybody who'd been observing since three Pacific time packed up their gear. Even with the sun low, the atmosphere was still calm and the sun not swimming around much if at all. But such increased atmosphere effects as we got pretty well ended any un-magnified observing for me; it had been easier when the sun was higher.

Okay, I can check this one off my Bucket List. Only time I'll ever mix a transit of Venus with a primary election. 8)

P.S.: Oh yeah -- only thing that could have made it better would have been "King of Pain" played on repeat on somebody's car player.
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