A transit of Venus was photographed in Hong Kong in 2004. The next transit of Venus will be June 5. The next one after that won't occur until 2117. (Photo via Wikimedia Commons)

A rare event will transpire in the sky June 5, and astronomers at the University of Missouri–St. Louis are inviting the public to watch.

The planet Venus will cross the face of the sun. It’s an occurrence that won’t repeat for more than a century – not until 2117.

“We will have a telescope set up with a solar filter on it for safe viewing,” said Erika Gibb, an associate professor of physics and astronomy at UMSL. The viewing will start at 5 p.m. at the Richard D. Schwartz Observatory on the UMSL campus, weather permitting.

Gibb will be on hand to answer any Venus transit or general astronomy questions.

People watching the event will observe Venus as a black disk moving across the sun.

Gibb discussed the twice-in-a-lifetime event on St. Louis Public Radio | 90.7 KWMU. She also spoke to the St. Louis Post Dispatch and NPR’s “Morning Edition.”

The viewing event is free and open to the public, and children are welcome.

The Richard D. Schwartz Observatory is located at Florissant Road and Rosedale Drive on UMSL’s campus. For directions and information about the observatory click here.