The 84-foot radio telescope dish is dismantled at Oak Ridge Observatory May 21. Although the facility is no longer listening for messages from other civilizations in our galaxy, a team is using an optical telescope there to search for possible laser-pulse messages from space. (Photos by Lisa Aciukewicz)

The Harvard-Smithsonian Center for Astrophysics may have closed down its program at the Oak Ridge Observatory on Pinnacle Road, but the search for extraterrestrial intelligence (SETI) continues at the site, led by Harvard University’s Paul Horowitz and his team. The program’s website offers a link stating, “Have we found aliens?” Clicking on this link––and who wouldn’t?––leads to a black page with three tiny white words in the upper left corner: “No, not yet.”

Horowitz’s SETI group has conducted its research at Oak Ridge since 1983, initially by listening for signals from space with an 84-foot radio dish, or radio telescope. Postdoctoral fellow Andrew Howard is active in the current project, which is called “All Sky Optical SETI Project” and which has been running for about a year. Howard explained that the dish was damaged by a wind storm in the late 1990s, at which point the optical phases of the project started, the most recent of which involved constructing a new telescope and a building to house it. Using the new 72-inch optical telescope, the team is looking for laser flashes from other civilizations in the Milky Way.

Speaking by telephone from his office in Cambridge, Howard said that the observatory serves as a “remote site.” Unlike previous SETI programs that required nightly observers on site, the team receives results by email each morning. “Everything is automated,” he said. “We don’t have to come out there, except for once or twice a month to make repairs or install new equipment.”

“Out there” is the observatory on Pinnacle Hill, which was constructed by Harvard University in 1933 to take advantage of both the elevation and the deep darkness of nights in the country. On April 28, 1956, the George R. Agassiz radio telescope was dedicated at the site. Describing the new telescope, originally built as an impressive 60-foot radio dish, the largest in this country at the time, David S. Heeschen wrote in the July 1956 issue of Sky & Telescope, “the research potential of this powerful new telescope is virtually unlimited.” In the 1970s, it was modified with an 84-foot dish acquired through the U.S. Army. Damaged and considered obsolete, the old dish was dismantled in late May.

The Center for Astrophysics (CfA) was founded as a joint venture of the Harvard College Observatory and the Smithsonian Astrophysical Observatory in 1973. Research highlights listed on the center’s website include a historic discovery made at Oak Ridge in 1988: “Observations at CfA’s Oak Ridge Observatory in Harvard, Massachusetts, provide first convincing evidence for a planet orbiting a star other than our own.”

Articles in the Boston Globe (“Lights Out,” June 28, 2005) and the Harvard Crimson (“Historic Telescope Takes Last Gaze Skyward,” August 5, 2005) cite light pollution as the primary cause of the decision to relocate the CfA program to Arizona, but David Aguilar, public affairs director for CfA, tells a different story. “It’s about the instruments,” he said in a telephone conversation. “We are using other facilities with newer and larger instruments.” He added with a laugh, “It’s also about the weather in Massachusetts. There are more clear nights in Arizona.”

As to what will happen to the rest of the instruments left on site, other than the new optical telescope being used by the Harvard SETI group, Aguilar said that these had been inventoried and categorized and a committee to decide their fate formed. He guessed that some would end up in a university collection of old science instruments. “From my understanding, Harvard does not sell their equipment,” he said. Robert Kirshner, the head of the committee, was on sabbatical and could not be reached for comment on the status of their decision-making.

Harvard University still owns the land, and in addition to the ongoing SETI research at the site, Howard said that the observatory is a remote site for a seismology group as well. Supported by the Harvard Geology Department and the U.S. Geological Survey, the seismology group is conducting research as part of a global network looking for earthquakes “felt all over the world.”

Meanwhile at the observatory, the search for intelligent life in outer space will continue. Howard said that they are looking for civilizations that are much older than ours. “We are infants in this game,” he explained. “Everyone we could talk to would be older.” He expressed the belief that with a bigger budget, they would be able to build a large pulse laser and send signals out into space. When asked if that was a possibility, he answered regretfully that it was not. “Anyway,” he added, “if we could send a message, what would we say? Who should speak for Earth?

“I’m hopeful that the SETI program will succeed on the whole in a generation,” Howard pronounced with enthusiasm. “It is valuable because while the chance of any one group having success is low, the impact of success would be enormous!