Campus Currents

Space Odyssey

Venus

Before dawn on June 8 at the Seacoast Science Center in Rye, N.H., about 100 people clustered around an array of telescopes set up on the lawn, a stone's throw from the pounding surf. Astronomy lecturer John Gianforte and UNH Observatory manager Matt Giguere attached a Meade ETX 90 telescope to a video feed and waited for sunrise and the transit of Venus. The last time Venus orbited between Earth and the sun was 1882.

As the sun rose, a ragged mauve layer of fog and sounds of foghorns hung over the ocean. Among the crowd were diehard spectators who had driven from as far away as Indiana and Texas. Lisa Urdanoff of Rye, N.H., had brought her young son, Morgan. "He knows all of his planets," she explained. Morgan added, "I know about their atmospheres, too."

Gianforte and others outlined transit history. First was Johannes Kepler, the 17th-century astronomer, who posed the then-heretical challenge to measure the distance from the Earth to the sun via observations of the transit. In the 18th-century, astronomers sailed to the far corners of the world in coordinated expeditions to answer Kepler's challenge. Their journeys took years, and their results were inconclusive.

Nearby, UNH physicist Jim Ryan adjusted his scope hopefully. He studies solar flares and gamma ray bursts, using data from orbiting telescopes. Thanks to radar, he noted, the distance from the Earth to the sun is now known to within a few meters. This event, sponsored in part by UNH's physics department and the observatory, was just for fun.

Nonetheless, staring at the fog, Gianforte said, "I'd take anything right now." At 6:30 a.m., the sun, shielded by thin clouds, finally appeared. Immediately, transit viewers tried on their donated sun shields, since gazing directly at the sun is harmful. Those with telescopes quickly switched filters. On the video feed, Venus, a tiny black beauty spot, clearly visible, moved at a fair pace.

"We're both going in the same direction," Gianforte explained to the rapt audience. "Venus at 23 miles per second, Earth at 18.6 miles per second." At 7:20, Venus began to pull away from the sun's fiery edge, creating a black teardrop. At 7:30, it was over. "Let's hear it for Venus!" cried Gianforte. Viewers, joining with fans of Venus around the world, clapped and cheered.

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