Monday, May 9, featured a rare transit of Mercury. How rare? The last one was in 2006 and the next one won’t happen until 2019. After that, you’ll have to wait until 2032 for another transit opportunity.
I viewed the transit from my home in Victoria, British Columbia, where we had perfectly clear skies. I used my 66-millimetre refractor (the same scope I used for the photo above) and it was the right tool for the job. I was impressed by how black the planet was compared with the umbra of the nearby spot group. I guess I shouldn’t be surprised really — the unlit side of Mercury is black while even the darkest part of a sunspot still throws off a lot of light. It was a treat watching the planet slip off the edge of the Sun, though by that time the seeing was beginning to get a bit wavy. A good show, even if it wasn’t as impressive as a Venus transit.