Barring the common late afternoon thunderstorms of June, Coloradans will get a rare chance to see the moon slide across the face of the sun during a partial solar eclipse on June 10.
Solar eclipses usually occur twice a year, but are not always visible from the United States, according to experts at Fiske Planetarium and Sommers-Bausch Observatory at the University of Colorado at Boulder. In fact, the next chance to see a solar eclipse in Colorado won't be until May 20, 2012, according to Robert Stoller, operations manager at Fiske Planetarium.
The June 10 eclipse will start about 6:20 p.m. when the moon begins to pass directly between the Earth and sun, according to Keith Gleason, coordinator of the Sommers-Bausch Observatory. The observatory will be open at 5 p.m. that day to allow the public safe viewing of the sun through its heliostat, a specialized solar telescope. The 16- and 18-inch telescopes also will be open for evening planet viewing.
"From our vantage point, it will appear as if a bite is mysteriously being taken out of the sun," Gleason said. He explained that maximum coverage of the sun will occur at 7:20 p.m., when 50 percent of the solar disc will be obscured. In Boulder, the sun will set behind the mountains at about 8 p.m., still partially eclipsed by the moon, he said.
Gleason warned that it is not safe for eclipse observers to attempt to view a partial solar eclipse with the naked eye, or through photographic negative film or virtually any other filter. The facilities at Fiske Planetarium and Sommers-Bausch Observatory are designed to allow the public to view this event safely in a variety of ways, including with specially filtered telescopes, pinhole projection viewers and official eclipse glasses, he said.
"Binoculars or telescopes that are not specifically designed and outfitted for viewing the sun can be dangerous," he said. "Permanent eye damage can easily result from improper viewing techniques."
After the eclipse, Fiske Planetarium will present a free star show about eclipses and upcoming celestial events. The observatory and planetarium will be open from 5 p.m. to 9 p.m.
Sommers-Bausch Observatory will be open Friday nights beginning at 9 p.m. during the summer for public use of its telescopes. Fiske Planetarium will host summer weekday matinees and Friday evening star and laser shows beginning in mid-June.
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