NEOSHIELD - A global approach to near-earth object impact threat mitigation

NEOShield, a project funded by the European Commission, brings together an international team of 13 partner organizations to address the global issue of near-Earth objects (NEO) impact prevention. The project's goals are to investigate the feasibility of techniques to prevent a potentially catastrophic impact on Earth by an asteroid or a comet and to develop detailed designs of appropriate missions to test deflection techniques. This chapter highlights some of the NEOShield research results obtained to date. The focus will be on mitigation-related science with a brief discussion of ongoing technology development and test-mission designs. Following a brief introduction to the NEOShield project, the three main NEO deflection techniques investigated are described (the kinetic impactor, blast deflection, and the gravity tractor), and the required or desirable payload instrumentation for each technique is discussed. A necessary prerequisite for the design of a successful deflection mission is accurate knowledge of the relevant physical properties of the threatening object; therefore, some of the key physical properties are addressed. A crucial component of NEOShield is laboratory and numerical modeling work to complement investigations of NEO physical properties based on observational data. Experiments to measure the momentum transfer during hypervelocity impacts into different asteroid analog materials are described, as well as initial results of numerical simulations of kinetic impacts at various velocities into small asteroids with different porosities.