1. M.I. Etchegaray, ed., Preliminary Scientific Rationale for a Voyage to a Thousand Astronomical Units, JPL Publication 87-17, Jet Propulsion Laboratory, Pasadena, Calif., 1987.
2. See, for example, National Research Council, The Decade of Discovery in Astronomy and Astrophysics, National Academy Press, Washington, D.C., 1991, pp. 100–109.
3. See, for example, J.O. Burns and W.W. Mendell, eds., Future Astronomical Observatories on the Moon, NASA Conference Publication 2489, National Aeronautics and Space Administration, Washington, D.C., 1988.
4. D.F. Lester, H.W. Yorke, and J.C. Mather, “Does the Lunar Surface Still Offer Value as a Site for Astronomical Observatories?” Space Policy 20: 99–107, 2004.
5. M.W Henley, J.C. Fikes, J. Howell, and J.C. Mankins, “Space Solar Power Technology Demonstration for Lunar Polar Applications,” 34th COSPAR Scientific Assembly, The Second World Space Congress, 2002, p. R-4-04.
6. M.W. Henley, S.D. Potter, J. Howell, and J.C. Mankins, “Wireless Power Transmission Options for Space Solar Power,” 34th COSPAR Scientific Assembly, The Second World Space Congress, 2002, p. R-4-08.
7. C. Alcock, R.A. Allsman, D. Alves, T.S. Axelrod, D.P. Bennett, K.H. Cook, K.C. Freeman, K. Griest, J. Guern, M.J. Lehner, S.L. Marshall, B.A. Peterson, M.R. Pratt, P.J. Quinn, A.W. Rodgers, C.W. Stubbs, and W.C. Sutherland, “First Observation of Parallax in a Gravitational Microlensing Event,” Astrophysical Journal Letters 454: 125, 1995.
8. A. Gould and B.S. Gaudi, “Femtolens Imaging of a Quasar Central Engine Using a Dwarf Star Telescope,” Astrophysical Journal 486: 687, 1997.
9. C. Maccone and G.L. Matloff, “SETIsail: A Space Mission to 550 AU to Exploit the Gravitational Lens of the Sun for SETI and Astrophysics,” Journal of the British Interplanetary Society 47: 3–4, 1994.
10. S.G. Turyshev and B.-G. Andersson, “The 550-AU Mission: A Critical Discussion,” Monthly Notice of the Royal Astronomical Society 341: 577–582, 2003.
11. President’s Commission on Implementation of United States Space Exploration Policy, A Journey to Inspire, Innovate, and Discover, U.S. Government Printing Office, Washington, D.C., 2004, p. 28.