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Easily retrievable objects among the NEO population


Asteroids and comets are of strategic importance for science in an effort to understand the formation, evolution and composition of the Solar System. Near-Earth Objects (NEOs) are of particular interest because of their accessibility from Earth, but also because of their speculated wealth of material resources. The exploitation of these resources has long been discussed as a means to lower the cost of future space endeavours. In this paper, we consider the currently known NEO population and define a family of so-called Easily Retrievable Objects (EROs), objects that can be transported from accessible heliocentric orbits into the Earth’s neighbourhood at affordable costs. The asteroid retrieval transfers are sought from the continuum of low energy transfers enabled by the dynamics of invariant manifolds; specifically, the retrieval transfers target planar, vertical Lyapunov and halo orbit families associated with the collinear equilibrium points of the Sun–Earth Circular Restricted Three Body problem. The judicious use of these dynamical features provides the best opportunity to find extremely low energy Earth transfers for asteroid material. A catalogue of asteroid retrieval candidates is then presented. Despite the highly incomplete census of very small asteroids, the ERO catalogue can already be populated with 12 different objects retrievable with less than 500 m/s of \(\Delta v\). Moreover, the approach proposed represents a robust search and ranking methodology for future retrieval candidates that can be automatically applied to the growing survey of NEOs.

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The authors wish to acknowledge Elisa Maria Alessi for her valuable comments and inputs to this work. The work was carried out making use of the Faculty of Engineering High Performance Computer Facility, University of Strathclyde; and was supported by European Research Council grant 227571 (VISIONSPACE).

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Correspondence to D. García Yárnoz.

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García Yárnoz, D., Sanchez, J.P. & McInnes, C.R. Easily retrievable objects among the NEO population. Celest Mech Dyn Astr 116, 367–388 (2013).

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  • Asteroids dynamics
  • Asteroid capture
  • Near-Earth Objects
  • Libration point orbits
  • Asteroid retrieval
  • Retrievable mass limit