The Earth’s surface bears the scars of 4.5 billion years of bombardment by asteroids, despite most having been erased by tectonic activity and erosion. Asteroids predominantly orbit the Sun in the asteroid belt between Mars and Jupiter, but a large number occupy orbits close to the Earth’s. These bodies are termed Near Earth Objects (NEOs) and they present a very real impact threat to the Earth. In 1998 NASA inaugurated the ‘Spaceguard Survey’ to catalogue 90% of NEOs greater than 1 km in diameter. The smaller bodies, meanwhile, remain undetected and far more numerous. In order to understand the NEO hazard, the consequences resulting from an asteroid impact require modelling. While the atmospheric entry of asteroids is a critical part of the impact process, it is the surface impact which is most important, both onto land and into the oceans. It is the impact generated effects (IGEs) that are hazardous to human populations on the Earth and the infrastructure they occupy. By modelling these IGEs and the consequences they present for humans and infrastructure, an understanding of the global vulnerability to the hazard is developed. ‘NEOimpactor’ is the software solution built to investigate the global vulnerability to NEO impacts. By combining existing mathematical models which describe the impact and effects, a unified impact simulator tool has been developed with the capacity to model the real consequences of any terrestrial impact. By comparing the consequences of multiple impact events, a complete vulnerability assessment of the global NEO hazard is derived. The result maps are designed for ease of dissemination to explain the impact risk to a non-specialist audience. The system has identified China, US, India, Japan and Brazil as facing the greatest overall risk, as well as indicating the various factors influencing vulnerability. The results can be used for informing the international decision making processes regarding the NEO hazard and potential mitigation strategies.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:500821 |
| Date | January 2009 |
| Creators | Bailey, Nicholas James |
| Contributors | Swinerd, Graham |
| Publisher | University of Southampton |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | https://eprints.soton.ac.uk/67323/ |
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