[meteorite-list] Brian Marsden, Eminent Astronomer and Comet/Asteroid Tracker, Dies

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Fri, 19 Nov 2010 12:42:16 -0800 (PST)
Message-ID: <201011192042.oAJKgGwW001855_at_zagami.jpl.nasa.gov>

http://www.cfa.harvard.edu/news/2010/pr201025.html

Press Release

Release No.: 2010-25
For Release: Thursday, November 18, 2010 12:00:00 AM EST

Brian Marsden, Eminent Astronomer and Comet/Asteroid Tracker, Dies

Cambridge, MA - Dr. Brian Geoffrey Marsden passed away today at the age
of 73 following a prolonged illness. He was a Supervisory Astronomer at
the Smithsonian Astrophysical Observatory and Director Emeritus of the
Minor Planet Center.

"Brian was one of the most influential comet investigators of the
twentieth century," said Charles Alcock, Director of the
Harvard-Smithsonian Center for Astrophysics, "and definitely one of the
most colorful!"

Dr. Marsden specialized in celestial mechanics and astrometry,
collecting data on the positions of asteroids and comets and computing
their orbits, often from minimal observational information. Such
calculations are critical for tracking potentially Earth-threatening
objects. The New York Times once described Marsden as a "Cheery Herald
of Fear."

The comet prediction of which Marsden was most proud was that of the
return of Comet Swift-Tuttle, which is the comet associated with the
Perseid meteor shower each August. Swift-Tuttle had been discovered in
1862, and the conventional wisdom was that it would return around 1981.
Marsden had a strong suspicion, however, that the 1862 comet was
identical with one seen in 1737, and this assumption allowed him to
predict that Swift-Tuttle would not return until late 1992. This
prediction proved to be correct. This comet has the longest orbital
period of all the comets whose returns have been successfully predicted.

In 1998, Marsden developed a certain amount of notoriety by suggesting
that an object called 1997 XF11 could collide with Earth. He said that
he did this as a last-ditch effort to encourage the acquisition of
further observations, including searches for possible data from several
years earlier. The recognition of some observations from 1990 made it
quite clear that there could be no collision with 1997 XF11 during the
foreseeable future.

Dr. Marsden also played a key role in the "demotion" of Pluto to dwarf
planet status. He once proposed that Pluto should be cross-listed as
both a planet and a "minor planet," and assigned the asteroid number
10000. That proposal was not accepted. However, in 2006 a vote by
members of the International Astronomical Union created a new category
of "dwarf planets," which includes Pluto, Ceres, and several other
objects. Pluto was designated minor planet 134340. This decision remains
controversial.

Marsden was born on August 5, 1937, in Cambridge, England. He received
an undergraduate degree in mathematics from New College, University of
Oxford, and a Ph.D. from Yale University.

At the invitation of director Fred Whipple, Dr. Marsden joined the staff
of the Smithsonian Astrophysical Observatory in Cambridge, Mass., in
1965. He became director of the Minor Planet Center in 1978. (The MPC is
the official organization in charge of collecting observational data for
asteroids and comets, calculating their orbits, and publishing this
information via Circulars.) Marsden served as an associate director of
the Harvard-Smithsonian Center for Astrophysics from 1987 to 2003 (the
longest tenure of any of the Center's associate directors).

Among the various awards he received from the U.S., the U.K., and a
handful of other European countries, the ones he particularly
appreciated were the 1995 Dirk Brouwer Award (named for his mentor at
Yale) from the American Astronomical Society's (AAS) Division on
Dynamical Astronomy, and the 1989 Van Biesbroeck Award (named for an old
friend and observer of comets and double stars), then presented by the
University of Arizona (now by the AAS) for service to astronomy.

Dr. Marsden married Nancy Lou Zissell, of Trumbull, Connecticut, on
December 26, 1964, and fathered Cynthia Louise Marsden-Williams (who is
now married to Gareth Williams, still MPC associate director), of
Arlington, Massachusetts, and Jonathan Brian Marsden, of San Mateo,
California. He also has three grandchildren in California: Nikhilas,
Nathaniel, and Neena. A sister, Sylvia Custerson, continues to reside in
Cambridge, England.

Dr. Marsden's full biography is available online
http://www.cfa.harvard.edu/pao/BrianMarsden.doc

Headquartered in Cambridge, Mass., the Harvard-Smithsonian Center for
Astrophysics (CfA) is a joint collaboration between the Smithsonian
Astrophysical Observatory and the Harvard College Observatory. CfA
scientists, organized into six research divisions, study the origin,
evolution and ultimate fate of the universe.

For more information, contact:

David A. Aguilar
Director of Public Affairs
Harvard-Smithsonian Center for Astrophysics
617-495-7462
daguilar at cfa.harvard.edu

Christine Pulliam
Public Affairs Specialist
Harvard-Smithsonian Center for Astrophysics
617-495-7463
cpulliam at cfa.harvard.edu
Received on Fri 19 Nov 2010 03:42:16 PM PST