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An ESA NEOCC Effort to Eliminate High Palermo Scale Virtual Impactors


In this work we summarize the initial results of a targeted effort of the ESA NEO Coordination Centre to obtain additional observational data in order to eliminate or reduce the impact probability estimate of a subset of the known near-Earth objects representing the highest fraction of the total known impact risk, as measured by the Palermo Scale.

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We would first like to thank David J. Tholen for allowing us to use his astrometric tools for some of the astrometric reductions which made this work possible and for telescope time he made available for one of these recovery campaigns, and Andrea Milani and Giovanni B. Valsecchi for the constant advice and scientific inputs on the most suitable and interesting targets in need of observations. We would also like to thank again Andrea Milani and Alan W. Harris (USA) for their very useful suggestions provided during the review process, and for an interesting first-person narration of how the idea of the targeted elimination of VIs was born, already fifteen years ago. We would also like to thank Richard J. Wainscoat, Peter Vereš and the entire PS1 consortium for the support with the archival precoveries in the Pan-STARRS database, and the creators and developers of the archival tools used for most of this precovery work. In particular this research made use of the facilities of the Canadian Astronomy Data Centre operated by the National Research Council of Canada with the support of the Canadian Space Agency, and the website developed by the SkyMorph team under NASA’s AISR program, a service of the Astrophysics Science Division at NASA/GSFC. Finally, the authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Mauna Kea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct and utilize observations obtained from this sacred mountain.

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Correspondence to Marco Micheli.

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Micheli, M., Koschny, D., Drolshagen, G. et al. An ESA NEOCC Effort to Eliminate High Palermo Scale Virtual Impactors. Earth Moon Planets 113, 1–13 (2014).

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  • NEO
  • Virtual impactor
  • Recovery
  • Precovery