The Observatory will be open for the transit, a celestial event in which the planet closest to our solar system's sun passes between the Earth and sun, casting a silhouette across the star's surface, starting at 7 a.m. Monday, May 9.
The transit of Mercury will last from approximately 7:12 a.m. to 2:42 p.m., with the moment of greatest transit at 10:58 a.m., and will be visible, weather permitting.
“As in any event that involves solar observation, never look directly at the sun without a well tested solar filter,” said Patrick Motl, associate professor of physics.
Motl also will discuss the transit at the Observatory’s monthly free open house, from 8 to 10 p.m. Sunday, May 8.
The transit of Mercury should only be observed using an instrument with an approved full-aperture solar filter to avoid serious eye damage. A safe alternative is to project the sun's image through a telescope or binoculars onto a white card. Never look at the sun without proper protection.
The safest and easiest way to view the transit is online, or in person at the Observatory. The silhouette of Mercury, which is 3,000 miles wide, will be too small to see with the naked eye -- a mere 1/158th of the sun's apparent diameter.
The transit begins before sunrise for observers in western North America and ends after sunset for Eastern Europe, Asia and most of Africa. Regions where the entire transit is visible include eastern North and South America, the Atlantic Ocean and Western Europe.
It will not be visible in eastern Asia, Japan, Indonesia, Australia and New Zealand.
The last time the planet Mercury passed between the earth and sun was November 8, 2006. The next transit of Mercury will not take place until November 11, 2019, after which it will take place only 10 more times this century.
IU’s Kirkwood Observatory in Bloomington will live stream the transit of Mercury at the IU Department of Astronomy website.
Both open houses are free and open to the public in the Observatory, 105 E. Rebecca Lane. Free parking is available on campus.
Indiana University Kokomo serves north central Indiana.