Transit of Sun by Mercury
November 22, 2006
The photo above shows Mercury transiting (crossing in front of) the Sun. This rather rare event occurred on November 8 and took nearly five hours -- beginning at 11:12 a.m. Pacific Standard Time. The entire solar disk is shown in order to better compare the sizes of the Sun and Mercury (black dot at lower center). Puny Mercury was even smaller than a sunspot. Compare it to sunspot #923, at the southwestern (left-hand) limb of the Sun. It's only about 10 arcseconds (1/360 of a degree) across, or just over 1/2 of 1 percent of the Sun's apparent diameter. Mercury is the planet closest to the Sun, and next to Pluto it's the smallest planet in our solar system. See the links below for more about Mercury's transit of the Sun.
Photo details: Nexstar 80GTL, Canon XTI, Prime Focus, 1/500 exposure.