Author Topic: The partial eclipse from Palo Alto  (Read 127 times)


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The partial eclipse from Palo Alto
« on: August 21, 2017, 11:05:14 AM »
     At first it looked like a complete cloud-out, but we got a fairly long break running from before to shortly after maximum eclipse. A small gathering of about 10 friends and neighbors got a good look at maximum eclipse of ca. 75%.

     The equipment in use consisted of a 60mm Coronado 0.5A-bandwidth hydrogen-alpha telescope, and one pair of eclipse glasses. 

     In the hydrogen-alpha, at 50X, one could see the roughness of the Moon's edge, i.e. the silhouette of the mountains on the Moon, plus the usual super-granulation on the Sun's surface.  The two sunspot groups and one large prominence, both of which the GONG website was showing to be there, were covered up by the Moon while we had our break in the clouds.  Seeing was surprisingly steady, very little if any noticeable "bouncing around" at 50X.


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Re: The partial eclipse from Palo Alto
« Reply #1 on: August 21, 2017, 08:14:00 PM »
I set up around 9:30 outside my workplace at Cupertino City Center. 80mm Stellarvue refractor and a 25mm plossl eyepiece, using eyepiece projection to display a bright 6" image. A few minutes later a co-worker arrived with a small reflector and a front filter. Other spectators brought assorted pinhole cameras and filter glasses. At peak eclipse time we had a crowd of about 200 people. A few dozen viewers saw the first sunspots reappear from behind the shadow, and a handful saw the last seconds of contact tick away.

Not a bad result for a rig that I cobbled together the day before. I had a few hours to test so I was pretty sure that nothing would overheat. I was willing to sacrifice the eyepiece if necessary. In the end I couldn't feel any heat buildup anywhere. My drive battery didn't work on site for some reason, but the eyepiece was low power so nudging the telescope every few minutes was feasible.