Mercury’s Transit Across the Sun: Nov. 15, 1999

At approximately 2:15 p.m. local Arizona time, the planet Mercury passed between the Earth and the sun in a rare shallow transit across the sun. A transit of this type has not occurred previously since the invention of the telescope, and is not expected again until the 23rd century. Deeper transits occur more frequently.

To get these shots, I constructed a home-made solar filter (see details) and placed it over the aperture of the telescope. The CCD camera was in the F10 position. I made a total of 36 exposures (0.02 seconds each) between 2:19 p.m.when I first located and identified Mercury’s intrusion on the Sun’s disk and 3:13 p.m. when it passed beyond the Sun. A sampling of those images are shown in sequence at the left.

Full Size View at Maximum Penetration

Follow Mercury as it moves across the sun


Time log of Mercury Transit

Earlier in the day, I achieved focus and practiced for this event by capturing a few sunspots, that are pretty impressive in their own right: