“A transit of Mercury is a rare celestial event: it is the observed passage of the planet Mercury across the disk of the Sun,” said OMSI astronomer and planetarium manager Jim Todd. “It occurs when Mercury, orbiting the sun ‘on the inside track,' catches up to and passes the slower Earth.”
For those viewing this movement of Mercury, the planet will appear as a small dot in the foreground, going from left to right across the southern portion of the sun. If the weather is permitting (and by the looks of forecasts it will be in this region), Todd said most of the world will be able to see this stellar wonder. A total of five and a half hours, the transit can be seen in the U.S., South America, Africa and Europe.