UND Observatory to host public viewing of rare celestial event

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News Article

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John D. Odegard School of Aerospace Sciences


The University of North Dakota Observatory will host a special public viewing of the transit of Venus, a rare celestial event that will be clearly visible in our region (weather permitting).

The public viewing will take place at a "Venus Transit" open house 3-7 p.m., Tuesday, June 5, at the UND Observatory. The facility will provide solar telescopes, glasses designed for solar viewing, activities for children and tours of the observatory.

"Venus is going to transit—or pass directly in front of—the sun, and this will be the last time in our lifetimes that we'll get this opportunity," said Paul Hardersen, associate professor in the UND Department of Space Science, part of the John D. Odegard School of Aerospace Sciences. Hardersen also manages the UND Observatory. The last transit of Venus was in 2004; the next pair of transits of Venus visible from Earth will be in 2115 and 2117.

According to the National Aeronautics and Space Administration's (NASA's) Venus transit website, since the apparent diameter of Venus is nearly 1 arc-minute, you can see the transit without optical magnification—but using solar filter protection—as it crosses the Sun. Nevertheless, the planet appears to be only 1/32 of the Sun's apparent diameter so a pair of binoculars or a small telescope at modest power will offer a much more satisfying view. All binoculars and telescopes must be suitably equipped with adequate filtration to ensure safe solar viewing (as noted above, the UND Observatory will have on hand suitable solar viewing filters and optical instruments).

The visual and photographic requirements for observing a transit are identical to those for solar viewing. Amateurs can make a scientific contribution by timing the four contacts at ingress and egress. Observing techniques and equipment are similar to those used for lunar occultations, NASA says.

Directions to the UND Observatory: From Grand Forks, take Highway 2 west, turn left (south) just past Mile Marker 346, turn right (west) at the T‐intersection, drive ½ mile west and take the first

left (south), and then ½ mile. The observatory is on the left (east side) of the road.