Astronomy in UP




Venus in Transit

Observation: Transit of Venus Observing conditions: Seeing: 6 (0-10 scale) Weather: Temperature 60º F, clear with small breeze Eyepieces: TeleVue 21mm plossl, William Optic's 24mm plossl Magnifications: 40x, 35x, 1x (naked eye)

The weather forecasts had bounced back and forth all week, from partly cloudy to thunderstorms; believe me I checked often. Because of this, I wanted to give myself enough time to find an alternate site if needed and so my adventure started at 3:00 am EDT. I checked the weather one last time before transit and satellite images showed clouds closing in from the northwest, diminishing any possibility of using my primary site near Munising overlooking Lake Superior. However, the skies just 50 miles to the south were clear and appeared to be out of the path of the front, so I headed out at about 3:30 EDT in search of a site along the Lake Michigan shoreline. I arrived in Escanaba Michigan just over an hour later and went down to the city park to check the available horizon. Escanaba juts out into Lake Michigan from the western shoreline and therefore the park had a clear view to the northeast across the waters of Bay de Noc. My trip had paid off.

After a short trip for a bagel and a re-supply of caffeine, I began setting up a little after 5:00 EDT with the transit about 50 minutes away. I brought three instruments: a Zeiss Telementor 63/840mm with a 40mm Coronado h-alpha filter, a Zeiss AS 63/840mm with Herschel wedge and Celestron 11X80 binoculars with Baader Astrosolar film. I had built the tube for the AS63 this winter with the idea of using it for the Venus transit. I felt that two scopes of the same aperture and focal length would provide good comparison images. I mounted the refractors side-by-side on a Vixen GPDX mount and used a TeleVue 21mm plossl in each for 40X and equal full disk views. With dawn eliminating any trace of stars, I aligned the mount using a compass and this proved to be more than adequate for the low power view. The binoculars were placed on a Bogen 501 head atop a Davis & Sanford tripod. I also had made up a handheld solar filter from Baader film and cardboard.

There was a thin line of clouds at the horizon (probably the clouds over Munising), but other than that the skies remained clear for the entire transit. The temperature was 60° F and there was a light breeze, really ideal conditions. At first I was alone, but by the time the transit had started, 4 individuals, who had heard about the event on the evening news the prior day, had joined me and we stood enjoying the early morning dawn in anticipation of something none of us had seen before.

Because on the horizon clouds, the sun did not appear until about two minutes after predicted sunrise, about 5:57 EDT. I was able to see it clearly in both scopes as soon as the rim peaked into view, but the Baader film on the binoculars prevented viewing until the sun was more than half in view. That didn't matter though, because the real target lay on the lower half of the sun. When Venus first made it's appearance at about 6:01, I was awe struck. My first thought was that it was bigger than I thought it would be and next that someone had used the sun as a target and shot a hole through it. Those thoughts continued as the sun rose and changed shape from a somewhat flattened orange oval to a round yellow-white disk. The seeing was as expected at such a low altitude, not good, but I didn't really care - it was clear and I was there for the event.

(Image - Venus transit in h-alpha - Zeiss 63mm refractor, William Optic's DCL28, Coronado SM40 h-alpha filter, Nikon Coolpix 990 camera)

All of us took turns looking at the three views, trying to decide which was most appealing. There were many exclamations of delight at what we were seeing. The sun was unusually quiet in h-alpha with very little surface detail and only a couple of tiny prominences barely rising from the limb. I'm sure if it had been active that this would have been everyone’s number one view, but now the small group of observers was mixed when it came to a favorite. I have to admit that I had a hard time deciding, but I usually stayed longer at the 11X80's. Maybe it was using both eyes or maybe the lower magnification or maybe the slow drift of a faint contrail across the sun that made the view so appealing, but it was mesmerizing. I tried a couple of times to image through the binoculars with a handheld camera, but was unsuccessful. We also took turns at using the handheld filter and trying to spot the planet, "naked eye". All of us were able to see a small speck of black on the "quarter-size" solar image.

I waited till everyone had their fill of views before attaching the camera to a telescope. I was using a Nikon Coolpix 990 coupled to a William Optic's DCL28, which is a 24mm plossl and yielded 35X in each scope. I like this setup because I can easily moved it from scope to scope. I made a few images in both "lights", but fully expected that the seeing would not yield the desired results. I particularly wanted a shot each in h-alpha and "white light" as a keepsake. I took quite a few images, but seeing wrecked most. I ended up with two h-alpha images - one of the full disk and a close up near 4th contact and a few white light images centered around 3rd contact.

(Image - Venus near 4th contact, h-alpha - Zeiss 63mm refractor, William Optic's DCL28, Coronado SM40 h-alpha filter, Nikon Coolpix 990 camera)

Third contact was at 7:06 EDT and twenty minutes later Venus was gone, nearly 90 minutes of transit in all. It was a remarkable experience, one that will long be remembered and well worth every effort. Tired, I began to pack up with a smile on my face.



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