NEOimpactor: a tool for assessing Earth's vulnerability to the NEO impact hazard

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

Name dc:type.qualificationname

Ph.D.

Level dc:type.qualificationlevel

doctoral

Grantor dc:publisher.institution

University of Southampton

Year dc:date.issued

2009

Author dc:creator

• Bailey, Nicholas James

Advisor dc:contributor.advisor

• Swinerd, G.S.