What could bring together a collection of faculty, historical scientific instruments, a band and a crowd of several hundred enthusiasts at 5 a.m.?

All participated in the Festival of the Transit of Venus, an event surrounding a rare astronomical occurrence that drew a community of astronomy fans to brave the early morning hours on Tuesday. Gathering at the Science Center, a diverse crowd observed the planet Venus traverse the disk of the Sun, and celebrated with a series of scientific and historical talks chronicling Harvard’s role in significant observations reaching back hundreds of years.

Observers viewed the event through the original telescope of Harvard astronomer John Winthrop, whose observations of a Venus transit in 1769 from Harvard Yard helped determine the distance from the Earth to the Sun.

Groups ventured to the roof of the Science Center to witness the transit first-hand using an array of historic and modern telescopes and observing equipment after sunrise at 5:09 a.m. Downstairs in Lecture Hall B, attendees waiting to view listened to talks highlighting the science of transits, Winthrop’s historic observations, and new applications of transits in cutting-edge research to detect extrasolar planets. Participants also watched a live projection from the roof of the transit-in-progress and live images from locations around the world. Some regions enjoyed more daylight hours for viewing.

The transits are highly rare events, occurring in pairs eight years apart with more than a century between the pairs. The most recent Venus transits occurred in 1761, 1769, 1874 and 1882. The next one will take place in 2012, again in the month of June.

The transit can be thought of as a mini-eclipse, with Venus appearing as a small black dot moving across the Sun’s surface and blocking a small portion of the Sun.

A CELESTIAL “ROCK CONCERT”

Harvard’s presentation was the brainchild of Sara J. Schechner ’79, Wheatland Curator of Harvard’s Collection of Scientific Instruments. Schechner, who has been studying Harvard’s early work in the sciences since her undergraduate years, said she went back into the archives this year to learn more about Winthrop and his transit observations, and came up with the idea of using his original apparatus to view the phenomenon in our own time.

After the Boston Globe featured a story on Winthrop and Harvard’s commemorations of his observations as the lead story in its science section last week, Sky and Telescope magazine and amateur telescope makers in Boston contacted Schechner to be part of the event.

“Suddenly I was looking at a very big event,” Schechner said. She said that she spent a lot of energy on logistics, including arranging to open the Greenhouse Cafe early, recruiting volunteers to help and obtaining radios for communication.

“It was like organizing a rock concert,” Schechner said.

In some ways, the comparison was literal.

An alum of the Harvard Band, Schechner asked the ensemble to play John Philip Sousa’s little-known “Transit of Venus March,” to add extra color to the scientific and historical aspects.

“It really was a wonderful team effort,” she said.

For Harvard Band members, playing the Sousa march was an interesting change of pace, despite a busy Commencement week schedule.