On May 9th, a rare space event will occur when Mercury's orbit comes between the Earth and the Sun. Mercury passes between the Earth and Sun only about 13 times a century, with its last trek occurring in 2006. Due to its small size, viewing this event safely requires a telescope or high-powered binoculars fitted with solar filters made of specially-coated glass. For those of us without access to this equipment, NASA has made provisions to check out the show.
Here's an animation from NASA of what this will look like:
Mercury will appear as a small black dot as it crosses the edge of the sun and into view at 7:12 a.m. The planet will make a leisurely journey across the face of the sun, reaching mid-point at approximately 10:47 a.m., and exiting the golden disk at 2:42 p.m. The entire 7.5-hour path across the sun will be visible across the Mid-Atlantic and Eastern United States.