Skull Valley • Though a rainstorm clouded the skies above Salt Lake City for the bulk of Tuesday afternoon, those dedicated enough to hop on Interstate 80 were treated to an unobstructed, once-in-a-lifetime view of the sun.

Venus made its way across the star's face in a transit that won't happen again until 2117.

"This is incredible," said Patrick Wiggins, NASA/JPL solar system ambassador to Utah. "We're part of history."

This was the seventh transit that was seen by people since German astronomer Johannes Kepler first predicted the phenomenon in the 17th century.

"When the [next transit] comes around, those of us now on the planet probably won't be then," Wiggins said.

Viewers could see the transit without the use of any magnification, but they did have to use special solar viewers to protect their eyes.

A seemingly perfect circle, no bigger than a beauty mark, made its way slowly across the upper-right quadrant of the sun.

Venus' transit is caused by a celestial alignment similar to last month's solar eclipse. The planet follows an orbit tilted to the Earth and the sun, but once every 100-plus years, that orbit aligns so viewers on Earth can see Venus cross the face of the sun twice in eight years. The last transit was in 2004, but was visible only from Europe and Asia.

For many Salt Lake City residents, driving into Skull Valley was well worth the trip.

Richard Bliss, a software engineer at Alliance Health in Salt Lake City, looked at the National Oceanic and Atmospheric Administration cloud map and decided to head west.

"I drove like a crazy person to get down here, and I'm obviously not the only crazy person," said the self-described science geek, signaling to the half-dozen cars gathered off Exit 77. "I love it, and it was totally worth it."

Peter Jensen drove out to complete the trifecta of recent celestial events that included the annular solar eclipse on May 20 and the partial lunar eclipse on Monday.

"I just enjoy it because it's reflective, it gives you a sense of scale," the Salt Lake City resident said. "Venus and Earth are about the same size, and seeing this gives you an idea of just how big the sun is."

Scores of viewers stood along I-80, looking through solar telescopes and binoculars, those in Salt Lake County were able to watch the transit — which started at 4 p.m. and continued past Utah's 9 p.m. sunset.

At 4 p.m. on Tuesday, the Utah Museum of Natural History had more than 1,300 paid admissions to look through solar telescopes set up by members of the Salt Lake Astronomical Society. Clouds again blocked those views until about a half-hour before sunset.

Seth Jarvis, director of Clark Planetarium, gathered with about 20 people at Dimple Dell Recreation Center in Sandy to "ooh and ahh" at the view, he said.

"We had to wait and we finally got a view," Jarvis said. "I've got people standing around me, and we're watching as it flickers in and out of the clouds."

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