A composite of the November 11, 2019 Transit of Mercury across the disk of the Sun, on a day with no sunspots on the Sun. The temperature was about -20° C to -15° C this morning but the sky was perfectly clear.

This takes in the last 3 hours of the 5.5-hour event starting at 8:05 a.m., just before mid-transit at 8:19 a.m. MST. The Sun rose at 7:50 a.m. MST this morning from my location in Alberta, Canada, with the transit in progress. But for the first few minutes the Sun’s image was so distorted from atmospheric turbulence that Mercury recorded only as a fuzzy blur. As it is, the disks of Mercury from early in the morning are soft and distorted.

The 37 images composited here start at 8:05 a..m. MST, at left, 12 minutes before mid-transit, and end with Mercury just beginning its egress of the disk at right at 11:02 a.m., with images for the composite selected at 5-minute intervals. I actually shot frames every 15 seconds for a time-lapse, for 700 images in total. The images are stacked in Photoshop with the Darken Color blend mode.

North is up here, with Mercury moving from left to right, east to west, across the Sun above the ecliptic which itself is angled up in relation to the cardinal directions.

All were with the Canon 60Da camera, and taken through the Astro-Physics 105mm apochromatic refractor with a 2X Barlow giving f/12 at 1200mm focal length, on an equatorial mount tracking the Sun, and through a Thousand Oaks metal-on-glass solar filter. The yellow tint on the Sun is what the filter provides.