Thomas Curwen

LOS ANGELES -- As night settles upon Mount Wilson, stars rise out of the December darkness and the wind begins to howl.

Brian Kloppenborg looks overhead. There's Polaris and in the northeast, the Big Dipper, all bright and twinkling to the naked eye, but to the telescopes on this summit, they are smudges, their light blurred by the blustery streams of air and dust. If this keeps up, observing tonight will be impossible.

"There," he says. "It's just to right of Capella. See it?"

He aims a flashlight high above a horizon of swaying pines and firs in the direction of a flickering star, faint enough to be easily overlooked.

"That's it -- Epsilon Aurigae," he says with an almost paternal air.

If he's disappointed by the conditions tonight, he's not showing it. He'll be up here for another night and he's been lucky so far. Since 2008, he has studied this distant neighbor of Earth with great success.

Lying in the swirls of the Milky Way 2,000 light-years away, Epsilon Aurigae (pronounced EP-si-lon au-RYE-gee) has long puzzled observers with its strange fluctuations of light. After seven visits to this summit, using one of the most sophisticated arrays of telescopes in the world, Kloppenborg, with the help of other astronomers, is slowly unraveling the mystery of this star.