Institute of Planetary Research Berlin-Adlershof

Section Physics of Small Bodies and Extrasolar Planets

Stereo View of the Inner Solar System on Wed. July 28, 1999
(the day asteroid 7737 was named Sirrah)

(7737) Sirrah = 1981 VU

"Discovered 1981 Nov. 5 by E. Bowell at the Anderson Mesa Station of the Lowell Observatory. Named in honor of Alan William Harris (b.1952), British astronomer, now at the DLR Institute of Planetary Exploration, Berlin. Harris has made both ground-based and space-based (ISO) radiometric observations of minor planets, concentrating especially on near-earth objects, and he has developed improved fitting techniques to relate observed fluxes to diameters and albedos. The name chosen is "Harris" spelled backwards, to distinguish from another Harris of the exact same name. Name suggested and citation prepared by the other A. W. Harris."

From Minor Planet Circular 35487, July 1999

(7737) Sirrah

Asteroid Named After "Backwards" DLR Scientist

After the planets formed some 4.5 billion years ago, some of the "building material" was left over in the form of asteroids and comets. These so-called minor planets are very important for solar system science in a number of respects. They hold many secrets concerning conditions in the early solar system and the processes governing planetary formation and solar system development. It is thought that these bodies may have played an important role in the initial development of life through the transport of water and organic molecules to the Earth. Furthermore, the destructive energy of asteroid and comet impacts may have influenced the subsequent progress of evolution.

Comets are icy bodies that originate in the outer regions of the solar system. Asteroids formed nearer to the Sun and are mainly rocky and/or metallic bodies. Most asteroids orbit in the so-called main asteroid belt which lies between the orbits of Mars and Jupiter. However, some small objects, which are probably mostly fragments arising from collisions between main-belt asteroids (but may also include the cores of dead comets), have orbits that cross those of the inner planets, including the Earth.

A special international conference called "Asteroids, Comets, Meteors" or ACM, held every three years, is the major forum at which researchers in these fields present and discuss their latest research results. The latest one was hosted by Cornell University at Ithaca, New York State, in July 1999.

It has become a tradition at the ACM conference dinner to announce new names of asteroids. New comets and asteroids are discovered frequently. Comets are named after their discoverers, while a newly discovered asteroid is initially given a sequential label until its existence and orbit become firmly established via repeated observations. It is then allocated a number and the discoverer has the privilege of naming it.

On November 5th, 1981, Ted Bowell, an astronomer at the Lowell Observatory in Arizona and discoverer of many asteroids, was able to add another one to his list: 1981 VU. After confirmation by other observations the asteroid received the number 7737 from the Minor Planet Center of the International Astronomical Union (IAU), the world's official planet naming authority.

At the ACM99 conference dinner Ted Bowell announced the names of his latest batch of asteroids. Included in his list was "Sirrah", for the asteroid 7737. The work which led to this honour (see citation above) is part of the programme of observations and modelling of asteroids and comets of the Physics of Small Bodies Section in the DLR Institute of Space Sensor Technology and Planetary Exploration in Berlin. The improved techniques developed by Dr. Alan Harris enable information on the surface properties, composition and sizes of asteroids, especially near-Earth asteroids, to be derived more accurately from astronomical observations. This information is important for a range of scientific questions concerning the origin and nature of near-Earth asteroids and in particular for the assessment of the risk that these objects pose as potential impactors on the Earth.

Other new asteroid names announced by Bowell at ACM99 honour scientists and engineers involved in NASA's Near Earth Asteroid Rendezvous mission (NEAR) , and astronomers and space scientists from Cornell University which hosted ACM99. Indeed, the host institution itself was honoured with Bowell's announcement that asteroid 1980 RP is to become 8250 Cornell !

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DLR Department of Planetary Exploration, 12489 Berlin, Germany