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Title: High energy density soft X-ray momentum coupling to comet analogs for NEO mitigation

Abstract

Here, we applied MBBAY high fluence pulsed radiation intensity driven momentum transfer analysis to calculate X-ray momentum coupling coefficients C M=(Pa s)/(J/m 2) for two simplified comet analog materials: i) water ice, and ii) 70% water ice and 30% distributed olivine grains. The momentum coupling coefficients (C M) max of 50×10 –5 s/m, are about an order of magnitude greater than experimentally determined and computed MBBAY values for meteoritic materials that are analogs for asteroids. From the values for comet analog materials we infer applied energies (via momentum transfer) required to deflect an Earth crossing comet from impacting Earth by a sufficient amount (~1 cm/s) to avert collision ~a year in advance. Comet model calculations indicate for C M = 5 × 10 –4 s/m the deflection of a 2 km comet with a density 600 kg/m 3 by 1 cm/s requires an applied energy on the target surface of 5 × 10 13 J, the equivalent of 12 kT of TNT. Depending on the geometrical configuration of the interaction the explosive yield required could be an order of magnitude higher.

Authors:
 [1];  [2];  [3];  [2]
  1. Harvard Univ., Cambridge, MA (United States); Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States)
  2. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
  3. Harvard Univ., Cambridge, MA (United States)
Publication Date:
Research Org.:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
1338313
Alternate Identifier(s):
OSTI ID: 1396481
Report Number(s):
SAND-2016-7126J
Journal ID: ISSN 0094-5765; PII: S009457651630772X
Grant/Contract Number:
AC04-94AL85000; FG52-09NA29457; NA0001804; NA0002937
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Acta Astronautica
Additional Journal Information:
Journal Volume: 129; Journal Issue: C; Journal ID: ISSN 0094-5765
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS

Citation Formats

Remo, J. L., Lawrence, R. J., Jacobsen, S. B., and Furnish, M. D. High energy density soft X-ray momentum coupling to comet analogs for NEO mitigation. United States: N. p., 2016. Web. doi:10.1016/j.actaastro.2016.09.026.
Remo, J. L., Lawrence, R. J., Jacobsen, S. B., & Furnish, M. D. High energy density soft X-ray momentum coupling to comet analogs for NEO mitigation. United States. doi:10.1016/j.actaastro.2016.09.026.
Remo, J. L., Lawrence, R. J., Jacobsen, S. B., and Furnish, M. D. Tue . "High energy density soft X-ray momentum coupling to comet analogs for NEO mitigation". United States. doi:10.1016/j.actaastro.2016.09.026. https://www.osti.gov/servlets/purl/1338313.
@article{osti_1338313,
title = {High energy density soft X-ray momentum coupling to comet analogs for NEO mitigation},
author = {Remo, J. L. and Lawrence, R. J. and Jacobsen, S. B. and Furnish, M. D.},
abstractNote = {Here, we applied MBBAY high fluence pulsed radiation intensity driven momentum transfer analysis to calculate X-ray momentum coupling coefficients CM=(Pa s)/(J/m2) for two simplified comet analog materials: i) water ice, and ii) 70% water ice and 30% distributed olivine grains. The momentum coupling coefficients (CM)max of 50×10–5 s/m, are about an order of magnitude greater than experimentally determined and computed MBBAY values for meteoritic materials that are analogs for asteroids. From the values for comet analog materials we infer applied energies (via momentum transfer) required to deflect an Earth crossing comet from impacting Earth by a sufficient amount (~1 cm/s) to avert collision ~a year in advance. Comet model calculations indicate for CM = 5 × 10–4 s/m the deflection of a 2 km comet with a density 600 kg/m3 by 1 cm/s requires an applied energy on the target surface of 5 × 1013 J, the equivalent of 12 kT of TNT. Depending on the geometrical configuration of the interaction the explosive yield required could be an order of magnitude higher.},
doi = {10.1016/j.actaastro.2016.09.026},
journal = {Acta Astronautica},
number = C,
volume = 129,
place = {United States},
year = {Tue Sep 27 00:00:00 EDT 2016},
month = {Tue Sep 27 00:00:00 EDT 2016}
}

Journal Article:
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