CCNet-ESSAY, 2 May 2000
"Attempts to interpret the IAU 'adoption' of the Scale as a
sanctification of every technical aspect of its first incarnation
or as an iron rule on its use in scientific studies of NEOs is,
first, misguided, and second, doomed to failure in the real world
-- Johannes Andersen, General Secretary of the IAU
THE TORINO SCALE - A WORKING ALTERNATIVE
By Jonathan Tate, Spaceguard UK
The Torino Scale a Working Alternative.
The Torino Impact Hazard Scale was devised by Professor Richard P.
Binzel of the Department of Earth, Atmospheric, and Planetary Sciences,
at the Massachusetts Institute of Technology (MIT). It has been
described as a "Richter Scale" for describing the impact hazard
associated with newly discovered asteroids and comets, and was designed
to serve as a communication tool for astronomers to describe the
seriousness of predictions of close encounters by asteroids and comets
to the public and media.
The Torino Scale uses numbers that range from 0 to 10, where 0
indicates that an object has a zero or negligibly small chance of
collision with the Earth. (Zero is also used to categorize any object
that is too small to penetrate the Earth's atmosphere intact, in the
event that a collision does occur.) A 10 indicates that a collision is
certain, and the impacting object is so large that it is capable of
precipitating a global climatic disaster.
The Torino Impact Hazard Scale is named after the Italian city in which
it was discussed, though not formally agreed, at the IMPACT workshop
(sponsored in part by the International Astronomical Union (IAU)) in
June 1999. Consensus was not achieved in Turin, and the IAU, while
welcoming the concept, has stated that "Attempts to interpret the IAU
'adoption' of the Scale as a sanctification of every technical aspect
of its first incarnation or as an iron rule on its use in scientific
studies of NEOs is, first, misguided, and second, doomed to failure in
the real world of science."
It is unlikely that such a scale will ever be needed in a professional
context, as those concerned are fully conversant with the subject. The
real value of an impact hazard scale comes into play when dealing with
disaster management organisations, the military, the media and the
public. To this end, any resulting scale must be simple (but not so
simple as to be misleading or confusing), easy to understand and as
accurate as possible.
The aim of this paper is to recommend a refinement of the Torino Scale
developed in the light of experience in dealing with other interested
organisations, the public and the media.
. . . [continued]
CCCMENU CCC for 2000