"This is a new century, and there's a new set of astronomical questions for which the transit can prove important," said Jay Pasachoff, an astronomer at Williams College in Williamstown, Mass. "With telescopes on the ground and in space, we can now use the transits to study things that had not been conceived of in the past."
Pasachoff has been lobbying his fellow astronomers to take the transit seriously, writing last month in the journal Nature that squandering the opportunity to collect as much data as possible would be "a crime."
Pasachoff is in position at the University of Hawaii's Mees Solar Observatory on the summit of Haleakala to observe the transit in its entirety and assess how the Venusian atmosphere polarizes sunlight. Astronomers on his team will be positioned around the world to take measurements with coronagraphs, spectrographs and the orbiting Solar Dynamics Observatory.
"We don't even know what we will find, and what the astronomers 105 years in the future will hope that we had observed," he said.
Désert, the Harvard researcher, is part of an international team that aims to collect similar data by pointing the Hubble Space Telescope toward the moon to analyze a blurry reflection of the transit. (The sun is too bright for Hubble's instruments to probe directly.)
Even scientists with no professional stake in the event said they would watch the skies Tuesday because the whole thing is just plain neat.
"I think for most of us there's a connection to the science we do, but it's mostly an opportunity to watch a rare and cool event, "said Caltech astronomer Heather Knutson, who studies exoplanets. "That's why many of us went into the field in the first place."
She said she would watch the transit on campus with students and members of the public. Barring cloudy weather, the transit will be visible in Los Angeles from 3:06 p.m. until sunset at 8:02 p.m.
Nina Misch, who manages the Cosmic Cafe, a glorified snack bar for weekend visitors to Mt. Wilson, said she would keep extended hours Tuesday for whatever business might come from the transit.
She sells eclipse shades for $1.35, and if the marine layer obscures viewing from the L.A. basin below, she is prepared to be busy.
Times staff writer Thomas Curwen contributed to this report.