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

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.