THE INTERNATIONAL SPACEGUARD INFORMATION CENTRE

28 January 2002

Spaceguard is the name given to an international effort to search the skies for asteroids that might collide with the Earth. The name was coined by Sir Arthur C Clarke in a 1973 novel that described how mankind set up an asteroid detection and defence network after a large asteroid struck Italy and devastated southern Europe. Since the novel was written the risks and grave consequences of asteroid impacts have been recognised and studied. Scientists around the globe are now working to ensure that Clarke's scenario of a sudden, deadly impact does not occur.

Rob McNaught from Siding Spring in New South Wales runs the only professional asteroid tracking project in the southern hemisphere. This operation is funded mostly by the United States and is associated with the Australian National University. It was set up in recognition of the need for Spaceguard telescopes in the southern hemisphere. Gordon Garradd, an astronomer from Loomberah in New South Wales, receives some funds from NASA for critical southern hemisphere follow-up observations using a home-made telescope.

However, a much greater search effort, including a larger telescope, is needed to detect asteroids that pass through southern skies. It would cost several million dollars to set up a suitable facility in Australia but some of this might be covered by contributions of equipment from the USA. Operational costs should be less than $1 million per year. This is a highly cost effective investment in the prevention of loss of life and severe economic damage from asteroid impacts.

McNaught and Garradd were previously in a team of Australian astronomers, led by Dr Duncan Steel, who searched for asteroids between the late 1980s and 1996. They found about one third of new threatening asteroids discovered during this period, demonstrating Australian expertise and the importance of searching southern skies. Australian government funding for the project was withdrawn in 1996 and the team disbanded.

The United Nations and the OECD have recognised the potential hazard to our civilisation from asteroid impacts. This month the OECD is looking at the issue as part of its Global Science Forum and recently asked developed nations to indicate their plans to contribute to the Spaceguard effort.

A major global Spaceguard effort could provide decades of warning prior to an impact. This would be sufficient time to refine the space technology needed to nudge a threatening asteroid into a harmless orbit, or to evacuate the predicted impact area. Without Spaceguard there would be too little warning to prevent a disaster. This is clearly demonstrated by the recent close approach of a 300m wide asteroid. It was discovered only a few days before it passed by the Earth and, had it been on a collision course, there is little that could have been done to prevent possibly millions of casualties when an area the size of Tasmania would have been devastated.

We note that a spokesperson for Science Minister Peter McGuaran said that the Government would look into renewing the funding of a dedicated Australian Spaceguard programme (The Age, 9th January). We welcome this reassessment of the issue and look forward to Australia rejoining the international effort to deal with the asteroid threat.