(meteorobs) BRIAN MARSDEN, EMINENT ASTRONOMER AND COMET/ASTEROID TRACKER, DIES

[Skywayinc at aol.com]

November 18, 2010
 
Contacts:
David Aguilar
+1  617-495-7462
_daguilar at cfa.harvard.edu_ (mailto:daguilar at cfa.harvard.edu)  
 
Christine Pulliam
+1 617-495-7463
_cpulliam at cfa.harvard.edu_ (mailto:cpulliam at cfa.harvard.edu)  
 
BRIAN MARSDEN, EMINENT ASTRONOMER
AND  COMET/ASTEROID TRACKER, DIES
 
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:
_http://www.cfa.harvard.edu/pao/BrianMarsden.doc_ 
(http://www.cfa.harvard.edu/pao/BrianMarsden.doc)  
 
Photos of Brian Marsden:
_http://www.cfa.harvard.edu/news/2010/pr201025_images.html_ 
(http://www.cfa.harvard.edu/news/2010/pr201025_images.html)  
 
                            # # #
 
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.
 
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