Image of the Mercury Transit


The fates conspired to keep from going to a star party this past weekend, where I had intended to shoot a full sequence of the Mercury transit so that I could combine them into a composite image showing the path of Mercury across the Sun.  The weather at home was predicted to be very cloudy, but I set up everything anyway, and was rewarded for my efforts with several long periods of sunshine.

I got about 200 frames with Mercury in various places along its path.  These could and should be combined to produce a less noisy image, but I shot these with a DSLR and I haven’t processed such images in such a long time that I don’t even have current software for it.  Instead, I selected a single frame (based on sharpness) and manually “cleaned it up”.

Mercury is the small, dark, well-defined spot near center top.  The large area with multiple dark shades near the bottom is a sunspot.  The two smaller dots above there might also be sunspots, but they might also just be dust specks on the image sensor – I can’t tell for sure.

Mercury “entered” on the right side of the Sun (as it appears in this photo) and traveled straight across to the upper left side.  The entry (called “first contact”) happened long before sunrise here, so I couldn’t have captured that anyway.  I did get some shots just prior to the “last contact”, but they are not very sharp.

If you missed it, you can probably find some videos online (try NASA’s website).  Or you can just wait until the next Mercury transit – in 2019!


About Greg Marshall

I am a retired electronics engineer and after a few months of enjoying my leisure I began to miss doing product development. My astronomy hobby always needed new solutions to unique problems, so I decided that whenever I came up with a good solution I would try to make it available to others.

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