Encounters of the kind we should be monitoring
Two staggering events have just occurred. The largest meteor to survive entry through the Earth's atmosphere in more than a century made impact. The exploding streak of light and resulting sonic boom occurred over a population centre in Russia and was captured on film from multiple angles. The surviving parts of the meteor that did not burn up on entry hit just outside of Chelyabinsk, a small industrial city almost the size of Adelaide.
Thousands were injured – mostly by flying glass from windows shattered by the impact – but no fatalities were reported because the impact was outside the city. If the meteorite had been larger or the impact zone in the centre of the city, the results would have been far more grave.
The second extraordinary space event occurred hours later when an asteroid passed about 27,000 kilometres above Earth or roughly a tenth the distance between us and the moon. ''The fly-by of 2012 DA14,'' according to NASA's Jet Propulsion Laboratory, ''is the closest-ever predicted approach to Earth for an object this large.'' Referring to the designated name given by the Minor Planet Centre of the International Astronomical Union, DA14 is estimated to be about a third the length of a football field or 50 metres in diameter.
"Due to limitations in telescopes and funding, we have mapped less than 1 per cent of metropolitan-threatening asteroids". Photo: NASA
Asteroids that size can destroy far in excess of the Hiroshima atomic bomb. Fortunately, over the past 15 years, NASA has mapped nearly 95 per cent of the largest civilisation-threatening asteroids that cross our orbit. Unfortunately, due to limitations in telescopes and funding, we have mapped less than 1 per cent of metropolitan-threatening asteroids. An impact of such an asteroid could have disastrous effects.
Following an influential 2008 report by a distinguished international panel of scientists, former astronauts, disaster management leaders, diplomats, and legal specialists, this issue was put squarely on the United Nations agenda. As a result, the threat of asteroid impact became a key topic of the Outer Space Scientific and Technical Subcommittee at the 50th session of the United Nations Committee on the Peaceful Uses of Outer Space, which began last week in Vienna. The so-called Action Team on Near-Earth Objects (NEOs) just submitted its ''recommendations for an international response to the near-Earth object impact threat'', which ''aims to raise awareness so that all nations are aware of potential future NEO threats and can co-ordinate mitigation activities''.
Australia should help co-ordinate these mitigation activities in the southern hemisphere. Not just because we are a sitting member of the UN Security Council, but also because of our unique global location. ''Australia is arguably the most advanced country in the hemisphere,'' wrote the first Australian-born astronaut, Philip Chapman, ''failure to contribute to the international effort is grotesquely irresponsible.''
Writing in an opinion piece in 2002, Chapman chided the one-time science minister Peter McGauran for dismissing an open letter to the Australian government from 91 international scientists. The letter was concerned about Australia's earlier decision to withdraw funding for its role in Spaceguard – the US-led congressionally mandated program focusing on international efforts to search, track, catalogue and ultimately mitigate all NEOs down to metropolitan-threatening sizes.
The $14 million in savings from the Howard government's decision to shut down our contribution to Spaceguard was made at the cost of Australia's greater contribution to the international community, to space science, and to global security writ-large. Previously, the Anglo-Australian Observatory was responsible for one-third of all NEO discoveries. Without Australia's concerted efforts, the global Spaceguard program suffers from a significant blind-spot.
In 2009, I had the privilege of teaming up with two former astronauts, an astrophysicist, and an engineer to write another open letter repeating the case that those 91 scientists did in 2002. The tepid reply stated that the Rudd government supported UN efforts to mitigate asteroid impacts and that it would ''consider its role in the international initiative'' when the ''Working Group on Near-Earth Objects will present a final report to the United Nations.'' Well it has. And it called for action.
Perhaps the Gillard government will finally listen.
David Robert Howell is a predoctoral fellow in International Security Studies at Yale University and a PhD Student in US Studies at Sydney University.