Monday, May 9, 2016

Mercury Transit - 2016

When I noticed earlier this year that the US east coast was in a good position for the May 9th transit of Mercury I made sure to put some placeholders into the work schedule - before work and around lunch time. One of the best perks of having a WFH ability is to take advantage of stepping away for an hour to run some errands - or catch a transit of the Solar System's innermost planet. A couple weeks prior I had purchased a filter for the Vixen (which has the added bonus of being yet another piece of paraphernalia in the tool chest for the August 2017 eclipse). However, we were in quite the rainy/overcast mode for weeks before so it seemed as though it'd be a missed opportunity.
The forecast indicated that the prospects would be best in the morning and then likely steadily deteriorate. The transit was due to start at about 7:10 a.m. with the Sun only about 10 degrees above the horizon. That would be challenging given the horizon.
I set up the Vixen and got the camera ready a little before 7. The sky had some clear sections but it looked like it was going to gradually worsen with high, thin clouds moving in. At first it seemed that a position just outside the front door would work, but the window of opportunity between trees proved to be inadequate. Finally the sunlight breaking at the end of the driveway guided me to a spot where I had a reasonable chance to observe for 20-30 minutes.
By the time I got the Sun targeted the transit was underway. And what a blank looking disk Sol exhibited - just one unimpressive sunspot formation to be seen. And there, at about the 11 o'clock position, was that unmistakeable circular pinprick of a shadow. I ran off multiple shots at a range of exposures, then spent a little time inspecting the minute ball using the 20mm eyepiece.
During the time I had multiple neighbors ask what I was up to, and the clouds carried out their threat to occlude the event so that by 8:30 I was back at my home office desk and ready to start the day. This is one of those events that is hardly spectacular yet for an astronomy wonk something you want to catch, highlighting the scale of our Sun compared to one of the smallest planets.
Mercury - tiny dot at about 11 o'clock