During the day on May 9th, the planet Mercury will pass across the face of the sun. The planet will be visible in telescopes properly equipped for solar observing as a small black dot moving across the sun. The transit will begin at 7:12 AM EST and will last until 2:42 PM. Transits of Mercury are not as rare as Venus, but they are infrequent; the last one was in 2006 and the next transit of Mercury will occur in November, 2019.
Observatory Park in Great Falls, Virginia will be open to the public for the transit from 7 AM to 3 PM. We will have telescopes with solar filters to properly observe the sun and the transit. Please stop by to observe part of the transit and any visible sunspots. DO NOT TRY TO OBSERVE THE TRANSIT WITHOUT PROPER SUN FILTERS. YOU CAN BE PERMANENTLY BLINDED.
For more information on the 2016 transit of Mercury, Sky and Telescope magazine has a helpful on-line article:
Other observing locations in western Maryland from the Westminister Astronomical Society include: