Little Woodchuck Observatory!

Mercury Transit - May 9th, 2016:

Monday, May 9th, 2016: from Cherry Springs State Park, PA.


CSSP is renown for it's dark, pristine night sky where views of the Milky-Way and Aurora can be seen.
While on a New-Moon observing trip, Along with a number of other astronomers I decided to stay an extra day for the Mercury Transit.

Eric L        and       Mike M

The alarm woke me at 6:00am, and with dawn lighting up the field, I headed back outside to setup my solar equipment.
Once I had the Daystar Ha filter and PST Cak ready to go, had to wait for the Sun to clear the trees along the eastern side of the observing field. It was going to be close, but by 7:05am, the Sun had made it over the last pine tree. I immediately focused the telescope and adjusted the cameras and shortly thereafter Mercury arrived on the limb of the Sun.
Mike M visually observed the planet passing in front of a limb prominence before touching the disk, Very Nice!!!
Eric, Mike and I were all very happy to see the start of the transit.

Here's my Camper setup and Equipment used:
8" Celestron Ultima SCT (f10). Daystar T-Scanner .6A H-alpha solar filter & StellaCam-3 1/2" CCD videocamera.
40mm Coronado PST Cak with a Sony Super HAD B&W CCTV 1/3" CCD videocamera.
and a 80mm f6.3 Kson Refractor with a 1000 Oaks WHite-light filter for visual observing, all on a Celestron CGem mount.


and a few "inside" pictures showing the video and computer monitors:


As I didn’t have a really good polar alignment from the night before, after about five minutes, the Sun showed a noticeably drift.
I ended up using a small ‘sticky note’ on the monitor screen with a hash-mark aligned to the one large sunspot as a sight indicator, utilizing the telescope hand-controller to lightly tweak the telescope back to the alignment mark when the mount had drifted too far.
This turned into my having to babysit the guiding for the entire seven hours of the transit!
I spent the day following the little planet as it slowly swept across the Sun, recording both Ha and Cak with my laptop, and Orion mini-DVR.

Daystar H-alpha pictures with the 8" SCT and StellaCam-3 videocamera:


2:11PM                 2:36PM

40mm Coronado PST Cak pictures with the Sony Super HAD videocamera:

7:14AM                 7:20AM

9:19AM                 9:51AM

11:36AM                 1:03PM


B&W timelaspse CaK video

During the initial ingress contact, I was too busy getting the video-capture running to really notice any transit phenomena.
But, there was more time during the final egress stage to notice a brief ‘blackdrop’ effect just prior to Mercury reaching the western limb.
Eric, Frank W from Pgh who had arrived mid-transit, and I also noticed an interesting effect where it appeared as if the Sun’s disk was bowing away from Mercury, as if the planet was pushing the limb forward, like a bow wake from a boat.

We also observed with the Daystar Ha video-feed Mercury passing over a low hedgerow of limb spicules, which allowed us to follow the planet for some additional time after it had officially left the Sun’s disk. Very Cool!!!!

Finally, around 2:30pm, Mercury sailed off the solar limb, back into darkness. Overall, while not quite as exciting as the Venus Transit, watching a transit of Mercury across the Sun was still an experience! One I was happy to observe and share.

Here's a couple of comparisons between Venus and Mercury showing the difference in their size.

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