Marsden, Brian

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Brian Marsden

Astronomer

Born Brian Geoffrey Marsden, August, 1937, in Cambridge, England; married Nancy Zissell, 1964; children: two. Education: Attended Oxford University; Yale University, Ph.D., 1965.

Addresses:

Office—Minor Planet Center, Smithsonian Astrophysical Observatory, 60 Garden St., Cambridge, MA 02138.

Career

Began working for Smithsonian Astrophysical Observatory, 1965; made head of Smithsonian's Central Bureau for Astronomical Telegrams, 1968; head of Smithsonian's Minor Planet Center, 1978—.

Member:

Chairman, American Astronomical Society Division on Dynamical Astronomy, 1976–78; president, International Astronomical Union Commission on the Positions and Motions of Minor Planets, Comets, and Satellites, 1976–79; board of directors, Spaceguard Foundation, 1996.

Awards:

Van Biesbroeck Award, University of Arizona, for services to astronomy, 1989; Brouwer Award, American Astronomical Society, for research in dynamical astronomy, 1995.

Sidelights

Brian Marsden is on the front line for new discoveries in space. As head of the Minor Planet Center at the Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, Marsden sifts through reports sent in from observatories around the world about unknown celestial objects. Marsden and his co–workers pore through thousands of astronomical observations every day, to confirm reports of new comets, asteroids, and supernovas. Marsden's office then publishes the International Astronomical Union (IAU) Circular, which serves as an official list of celestial discoveries. "If it moves or it's fuzzy, it goes through us," he told Astronomy magazine's David H. Freedman and Robert Naeye. Amateur astronomers as well as the biggest observatories in the world send in their suspicious sightings to Marsden. Marsden caught the world's attention in 1998, when he warned that a newly discovered asteroid might come dangerously close to the earth in the year 2028. As the clearinghouse for new celestial sightings, it was Marsden's job to disseminate this bad news. He was also able to gather enough new information within 24 hours that he could offer a revised calculation. This one showed the asteroid zooming safely past the earth. Anyone worried about cataclysmic collisions or eager to name a new comet must pay attention to Marsden.

Marsden was born in Cambridge, England, in August of 1937. While still in high school, Marsden became an expert on calculating the initial orbits of newly discovered comets. Young as he was, there were only a few other people in the world who could manage these laborious calculations. A member of the British Astronomical Association befriended Marsden, and lent him a large mechanical calculator. With this bulky machine and a logarithm table, the young man worked away at the difficult orbital formulations. He did his undergraduate work at Oxford University, and then in 1959 enrolled at Yale University's graduate program in celestial mechanics. Yale was one of the few places offering advanced work in this field. Marsden wrote his dissertation on the orbits of the Galilean satellites of Jupiter, and received his Ph.D. in 1965.

Though Marsden had found few compatriots who shared his interest in comets and asteroids, the United States was beginning to pour money into astronomy programs. After the Soviet Union successfully launched its Sputnik satellite in 1957, the United States government began its race to get into space. In 1965, Marsden accepted a position at one of the most flourishing centers of celestial research, the Smithsonian Astrophysical Observatory, an institution affiliated with Harvard University. That year, the Smithsonian Astrophysical Observatory also became home to the Central Bureau for Astronomical Telegrams, a research clearinghouse that had been based in Copenhagen, Denmark, since the 1920s. In 1968, Marsden became head of this organization. In 1978, Marsden also became head of the Minor Planet Center. The Minor Planet Center had been based in Cincinnati, Ohio, since 1947, but it moved to Cambridge under the aegis of the Smithsonian. The Minor Planet Center's mission was to catalog discoveries and observations about small orbiting bodies such as asteroids.

The Minor Planet Center and the Central Bureau for Astronomical Telegrams function as the news service for celestial events. All new discoveries come through these offices. Marsden's offices publish circulars that list new asteroids, comets, and newly determined orbits, and prints predictions of events such as a comet colliding with Jupiter. Marsden's personal interest was in conducting an inventory of the solar system, and he also rediscovered some so–called lost comets. Marsden predicted the return in 1992 of comet Swift–Tuttle, which was last seen in 1862. Marsden also became known in the 1980s for his contention that Pluto was not a planet and should be reclassified as an asteroid. Marsden was not alone in holding this opinion, but he was out-spoken in this rather unpopular cause. But Marsden really grabbed headlines with his ominous predictions of possible collisions of comets or asteroids with the earth. Most scientists now believe that some kind of celestial object colliding with the earth led to the demise of the dinosaurs. Early in the twentieth century, an asteroid or comet 100 meters wide struck the earth, causing massive damage in remote Siberia. As the breaking news service for celestial bodies, Marsden several times warned of impending close calls. In 1983, Marsden verified that a comet known as IRAS–Araki–Alcock would pass closer to the earth than any known comet (except one that had passed in 1770). Knowing that such news causes alarm, Marsden told John Noble Wilford of the New York Times that there was "Nothing to fear." However, in 1998, Marsden came up with a prediction that was not so comforting. Marsden's office issued a circular on March 11, 1998, noting that an asteroid known as 1997 XF11 was in a possible collision course with the earth, and could hit in 2028. Even though the possible collision was 30 years away, and Marsden judged the actual chance of a collision as very small, his announcement sparked fearful news stories around the globe. Marsden's office called for more data, and within 24 hours, it received a photograph that gave some more information on the comet's orbit. Using the data from the photograph, Marsden recalculated the course of 1997 XF11, and found that it would pass well clear of the earth. Marsden dealt with the crisis quickly, but the incident did call attention to his organizations, and ultimately attracted more funding. Several organizations, including the Space-guard Foundation, which Marsden once headed, now focus on finding so–called near–earth objects (NEOs) that might pose a threat to the planet.

Marsden works long hours with only a very small staff for support. Now in his sixties, Marsden is considering retiring. On the other hand, some of his colleagues believe that he is not nearly ready to retire. He is too good at what he does, and his position is too crucial. Marsden would like to see more money spent on new telescopes that can spot smaller NEOs. He also recommends that scientists plan now for what to do if a comet or asteroid is found that really is on a collision course with the earth. He told Steve Nadis of Scientific American that "we have to do more than the dinosaurs."