Venus Transit at Washburn & Space Place

Jun 07, 2012

Above: Long lines formed throughout the afternoon to see the Venus Transit at Washburn Observatory

Hundreds of people gathered at UW-Madison’s historic Washburn Observatory and at the Astronomy Department’s Space Place Tuesday night to view the transit of Venus.

In this rare astronomical event, the planet Venus crosses the disk of the Sun, blocking just a little bit of Sun light, as can be seen in the images taken at Washburn. The Earth's and Venus' orbits line up so that Venus appears as a dark dot that slowly crosses the Sun over the course of several hours. It is much like a solar eclipse, except that Venus is too small to darken the Sun completely, as the moon would during a solar eclipse.

Above: The telescope projected the image of the transit onto a screen for people to view.

At Washburn Observatory, the public was able to view the transit with the newly refurbished 15.6-inch refracting telescope, as well as other dedicated telescopes set up outside. At Space Place, people could view the transit through telescopes out on the lawn or watch a live webcast in the lecture hall.

“We had an incredible turnout—perhaps 500 people at Washburn throughout the event,” says graduate student Paul Sell. “People appreciated the significance of the transit and felt awe toward what they saw,” adds scientist Eric Hooper. At Space Place, nearly 400 visitors came to see the transit. “We had seven telescopes set up and three specialized ‘sunspotter’ type telescopes available,” says Director Jim Lattis. “Solar viewers sold out almost immediately.”

Transits of Venus are rare events. This is only the second, and last, such transit visible this century. They occur in pairs, with eight years separating the transits in each pair. The first in the current pair occurred in June 2004; the last one before that was in December 1882. And after this year's event, the next transit of Venus will not occur until December 2117.

The historic Washburn Telescope is among the handful of operational public telescopes to observe both the 1882 and the 2012 eclipses, and with a little luck, it will do so again in 2117.


Above: Professor Heinz demonstates how big the Sun is in relation to the image (the small circle is the area of the Sun visible by the telescope under magnification).

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