A Caltech Library Service

Long-period comet impact risk mitigation with Earth-based laser arrays

Zhang, Qicheng and Lubin, Philip M. and Hughes, Gary B. (2017) Long-period comet impact risk mitigation with Earth-based laser arrays. In: Astronomical Optics: Design, Manufacture, and Test of Space and Ground Systems. Proceedings of SPIE. No.10401. Society of Photo-Optical Instrumentation Engineers , Bellingham, WA, Art. No. 1040104. ISBN 9781510612594.

[img] PDF - Published Version
See Usage Policy.


Use this Persistent URL to link to this item:


Long-period comets (LPCs) frequently transit the inner solar system, and like near-Earth asteroids (NEAs), pose a continued risk of impact with Earth. Unlike NEAs, LPCs follow nearly parabolic trajectories and approach from the distant outer solar system where they cannot be observed. An LPC on an Earth-impact trajectory is unlikely to be discovered more than a few years in advance of its arrival, even with significant advancements in sky survey detection capabilities, likely leaving insufficient time to develop and deliver an interception mission to deflect the comet. However, recent proposals have called for the development of one or more large ∼ 1 km laser arrays placed on or near Earth primarily as a means for photon propulsion of low-mass spacecraft at delta-v above what would be feasible by traditional chemical or ion propulsion methods. Such a laser array can also be directed to target and heat a threatening comet, sublimating its ices and activating jets of dust and vapor which alter the comet's trajectory in a manner similar to rocket propulsion. Simulations of directed energy comet deflection were previously developed from astrometric models of nongravitational orbital perturbations from solar heating, an analogous process that has been observed in numerous comets. These simulations are used together with the distribution of known LPC trajectories to evaluate the effect of an operational Earth-based laser array on the LPC impact risk.

Item Type:Book Section
Related URLs:
URLURL TypeDescription
Zhang, Qicheng0000-0002-6702-191X
Hughes, Gary B.0000-0003-4739-8493
Additional Information:© 2017 SPIE. We gratefully acknowledge funding from the NASA California Space Grant NNX10AT93H and from NASA NIAC NNX15AL91G and NNX16AL32G as well as a generous gift from the Emmett and Gladys W. Fund in support of this research. GNU Parallel was used in generating the presented simulation results.
Funding AgencyGrant Number
Emmett and Gladys W. FundUNSPECIFIED
Subject Keywords:comets, high-powered lasers, phased-array optics, planetary defense
Series Name:Proceedings of SPIE
Issue or Number:10401
Record Number:CaltechAUTHORS:20180502-160743580
Persistent URL:
Official Citation:Qicheng Zhang, Philip M. Lubin, Gary B. Hughes, "Long-period comet impact risk mitigation with Earth-based laser arrays", Proc. SPIE 10401, Astronomical Optics: Design, Manufacture, and Test of Space and Ground Systems, 1040104 (8 September 2017); doi: 10.1117/12.2274726;
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:86203
Deposited By: Tony Diaz
Deposited On:03 May 2018 21:09
Last Modified:09 Mar 2020 13:18

Repository Staff Only: item control page