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Safely View the Transit of Venus June 8 With Help of UNH Space Scientists
DURHAM, N.H. -- On Tuesday, June 8, the University of New Hampshire Observatory and Department of Physics, along with Rivers Camera, will sponsor a sunrise event at the Seacoast Science Center to view the passage, or transit, of Venus across the face of the Sun. No living person has seen this event, which last occurred in 1882 and was the focus of intense scientific scrutiny.

On the East Coast, the planet, which will appear as a small black dot with a diameter one thirty-second of the Sun's, will already be making its transit as the Sun rises around 5 a.m. The event will end roughly two and a half hours later. Special telescopes and solar sunglasses for safely viewing the transit will be provided. UNH staff will also be on hand to answer questions.

The transit of Venus occurs in pairs nearly every century. The last transits occurred in 1874 and 1882. After next week, Venus will again cross the Sun on June 6, 2012.

In 1882 it was hoped that scientific observation of the transit would help answer one of the most fundamental questions of the day: What is the exact distance between the Earth and the Sun? This number, in turn, would have provided scientists with the ability to calculate the size of the solar system using formulas developed by astronomer Johannes Kepler in the 17th century. At the time the United States sent out eight expeditions to make observations around the world, and other nations took similar steps.

But a precise number could not be determined because of, in part, the so-called "black drop" effect, which makes it appear as if Venus deforms and clings to the edge of the Sun as it begins and finishes its transit. Scientists now know that viewing the event through Earth's atmosphere and the limitations of optical equipment causes the black drop effect. Also, the exact distance to the Sun and other planets has since been measured precisely using radar and laser ranging techniques.

Of course, viewing any type of solar event, such as a solar eclipse or the transit of Venus, must be done with great care to avoid severe eye damage or even blindness. The Sun should never be viewed with the naked eye. Permanent eye damage can occur almost instantly. Sunglasses, unfiltered telescopes, binoculars, cameras, even cloud cover do not provide adequate protection.

The Seacoast Science Center is located at 570 Ocean Blvd. in Rye. For more information about the June 8 event, call the Science Center at (603) 436-8043 or
e-mail John Gianforte at Poor weather conditions will cancel the session. For more information on the transit of Venus, visit the NASA web site at

David Sims
Science Writer
Institute for the Study of Earth, Oceans, and Space
(603) 862-5369