(1) Istituto di Astrofisica Spaziale--Planetologia, Rome, Italy.
(2) National Astronomical Observatory, Tokyo, Japan.
(3) Harvard-Smithsonian Center for Astrophysics, Cambridge, MA, USA.
(4) Observatory, University of Helsinki, Finland.
(5) Lowell Observatory, Flagstaff, AZ, USA.
(6) Department of Physics, University of Adelaide, Australia.
Over the past five years there has been much discussion and debate with regard to the hazard posed to humankind by the occasional catastrophic asteroid/comet impact upon the Earth. The chance of such an event occurring within the next century is small, but the consequences are horrendous, meaning that we must take the possibility seriously: this is one area of astronomical science where our knowledge has real and immediate consequences for the whole of humanity.
The International Astronomical Union formed a Working Group on Near-Earth Objects in 1991, that group producing an interim recommendation in 1994, with a final report due in 1997. In the USA, various NASA committees have made recommendations to Congress with regard to the type of search program required in order to give an answer to the question `Will a major impact occur in the foreseeable future?' Such a program would need 10--20 years to find the vast majority of large Earth-approaching bodies and determine their orbital parameters with the required precision, a positive answer then necessitating the implementation of a major space project to divert the potential impactor; in the longer term it would be necessary to continue to patrol for dangerous long-period comets, and smaller near-Earth objects. In various other countries efforts have been begun to contribute to what must be a international effort.
On 1996 March 20th, the Parliamentary Assembly of the Council of Europe passed a motion calling upon its 35 member states, and ESA, to contribute to this burgeoning global program. The motion also suggested that The Spaceguard Foundation assist and coordinate the work on this major project being carried out by the different nations around the world. In this paper the aims and actions of The Spaceguard Foundation will be outlined, the prospects for the next few years discussed, and the opportunities for involvement by professional and amateur astronomers from all countries emphasized.
For further information, see the WWW home page of The Spaceguard Foundation: http://www.brera.mi.astro.it/SGF/
(*) Member of the Board of Directors, The Spaceguard Foundation, Rome, Italy