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Investigating nearby exoplanets via interstellar radar

  • Louis K. Scheffer (a1)


Interstellar radar is a potential intermediate step between passive observation of exoplanets and interstellar exploratory missions. Compared with passive observation, it has the traditional advantages of radar astronomy. It can measure surface characteristics, determine spin rates and axes, provide extremely accurate ranges, construct maps of planets, distinguish liquid from solid surfaces, find rings and moons, and penetrate clouds. It can do this even for planets close to the parent star. Compared with interstellar travel or probes, it also offers significant advantages. The technology required to build such a radar already exists, radar can return results within a human lifetime, and a single facility can investigate thousands of planetary systems. The cost, although too high for current implementation, is within the reach of Earth's economy.

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ACMA (2012). Planning for the Radio Astronomy Service. URL:
Alber, C., Ware, R., Rocken, C. & Solheim, F. (1997). GPS surveying with 1 mm precision using corrections for atmospheric slant path delay. Geophysical Research Letters 24(15), 18591862.
Beichman, C.A., Johnston, K.J., Bally, J., Kaltenegger, L., Rttgering, H., Serabyn, E. & Crisp, D. (2006). Terrestrial Planet Fnder Interferometer -Planetary Detection and Characterization. URL:
Black, G. (2010). A global map of Titan's 13 cm wavelength radar reflectivity, in Bulletin of the American Astronomical Society, vol. 42, p. 1064.
Butler, B., Muhleman, D. & Slade, M. (1993). Mercury: full-disk radar images and the detection and stability of ice at the north pole. Journal of Geophysical Research 98(E8), 1500315015.
Butrica, A. (1996). To See the Unseen: A History of Planetary Radar Astronomy. p. 1. National Aeronautics and Space Administration, Washington, DC.
Campbell, D., Black, G., Carter, L. & Ostro, S. (2003). Radar evidence for liquid surfaces on Titan. Science 302(5644), 431434.
CSIRO (2008). CSIRO Lets Major Antenna Contract for ASKAP. URL:
Davarian, F. (2007). Uplink arrays for the deep space network. Proceedings of the IEEE 95(10), 19231930.
Dewdney, P., Hall, P., Schilizzi, R. & Lazio, T. (2009). The square kilometre array. Proceedings of the IEEE 97(8), 14821496.
Dixon, T. (1991). An introduction to the Global Positioning System and some geological applications. Reviews of Geophysics 29(2), 249276.
Drake, S. (1993). Radio emission from coronal-type stars. In Physics of Solar and Stellar Coronae: GS Vaiana Memorial Symposium, pp. 393400. Springer, Palermo, Italy.
Gardiol, D., Busonero, D., Gai, M. & Lattanzi, M. (2005). Gaia performance on bright stars. In SWG7 Meeting, pp. 24. Paris.
Goldsmith, P. (1996). The second Arecibo upgrade. Potentials, IEEE 15(3), 3843.
Harmon, J. (2002). Planetary delay-doppler radar and the long-code method. Geoscience and Remote Sensing, IEEE Transactions on 40(9), 19041916.
Harmon, J., Arvidson, R., Guinness, E., Campbell, B. & Slade, M. (1999). Mars mapping with delay-doppler radar. Journal of Geophysical Research 104(E6), 1406514089.
Harmon, J., Perillat, P. & Slade, M. (2001). High-resolution radar imaging of Mercury's north pole. Icarus 149(1), 115.
Kayton, M. & Fried, W. (1997). Avionics Navigation Systems. Wiley-Interscience, New York, New York, USA.
Laing, R., Riley, J. & Longair, M. (1983). Bright radio sources at 178 mHz-flux densities, optical identifications and the cosmological evolution of powerful radio galaxies. Monthly Notices of the Royal Astronomical Society 204, 151187.
Levine, M., et al. (2009). Terrestrial Planet Finder Coronagraph (TPF-C) flight baseline concept, arXiv: 0911.3200.
Lindegren, L. (2009). Gaia: astrometric performance and current status of the project. In Proceedings IAU Symposium No 261, Relativity in Fundamental Astronomy. Cambridge University Press, Virginia Beach, Virginia, USA.
Long, M. (1975). Radar Reflectivity of Land and Sea, p. 1. DC Heath and Co., Lexington, Mass.. 390.
Malerba, F. (1992). Learning by firms and incremental technical change. Economic Journal 102, 845859.
Martin, S., Ksendzov, A., Lay, O., Peters, R.D. & Scharf, D.P. (2011). TPF-Interferometer: a decade of development in exoplanet detection technology. In SPIE Optical Engineering+ Applications, pp. 81510D81510D. International Society for Optics and Photonics.
Matthews, C.M. (2012). The Arecibo Ionospheric Observatory, Technical report, Congressional Research Service. URL:
Muhleman, D., Grossman, A. & Butler, B. (1995). Radar investigations of Mars, Mercury, and Titan. Annual Review of Earth and Planetary Sciences 23, 337374.
Nan, R. (2008). Introduction to FAST-five hundred meter aperture spherical radio telescope. In Proc. of SPIE, Vol. 7012, pp. 70121E–1.
Nash, D. (2011). The Hyg Database. URL:
Ostro, S. (1993). Planetary radar astronomy. Reviews of Modern Physics 65(4), 1235.
Pettengill, G. & Dyce, R. (1965). A radar determination of the rotation of the planet Mercury. Nature 206, 1240.
RECONS (2012). The one hundred nearest star systems. The Research Consortium on Nearby Stars. URL:
Reid, I., Gizis, J. & Hawley, S. (2007). The Palomar/MSU nearby star spectroscopic survey. IV. The luminosity function in the solar neighborhood and M dwarf kinematics. The Astronomical Journal 124(5), 2721.
Renzetti, N.A., Thompson, T.W. & Slade, M.A. (1988). Relative planetary radar sensitivities: Arecibo and Goldstone. Technical Report TDA 42–94, JPL. URL:
Rogers, A., Ingalls, R. (1969). Venus: mapping the surface reflectivity by radar interferometry. Science (New York, NY) 165(3895), 797.
Rogstad, D.H. (2005). The SUMPLE algorithm for aligning arrays of receiving radio antennas: coherence achieved with less hardware and lower combining loss. Technical Report 42162. URL:
Ruze, J. (1966). Antenna tolerance theory - a review. Proceedings of the IEEE 54(4), 633640.
Rzhiga, O. (1985). Radar studies of other planetary systems? Astronomich-eskii Zhurnal 62, 500505. Translation into English by R.B. Rodman at….29..290R.
Scheffer, L. (2005). A scheme for a high-power, low-cost transmitter for deep space applications. Radio Science 40(5), RS5012.
Shao, M., Catanzarite, J. & Pan, X. (2010). The synergy of direct imaging and astrometry for orbit determination of exo-earths. Astrophysical Journal 720(1), 357.
Simpson, R., Harmon, J., Zisk, S., Thompson, T. & Muhleman, D. (1992). Radar determination of Mars surface properties. Mars 1, 652685.
Stacy, N., Campbell, D. & Ford, P. (1997). Arecibo radar mapping of the lunar poles: a search for ice deposits. Science 276(5318), 15271530.
Thompson, T. (1987). High-resolution lunar radar map at 70-cm wavelength. Earth, Moon and Planets 37(1), 5970.
Tuomi, M., et al. (2012). Signals embedded in the radial velocity noise: periodic variations in the τ Ceti velocities. Astronomy and Astrophyics 551(3), A79. URL:
Williams, F. (1985). A radar for the exploration of exstrasolar planets. Proceedings of the IEEE 73(2), 355361. Note: The misspelling in the title is in the original.
Yelle, L. (1979). The learning curve: historical review and comprehensive survey. Decision Sciences 10(2), 302328.
Zisk, S., Pettengill, G. & Catuna, G. (1974). High-resolution radar maps of the lunar surface at 3.8-cm wavelength. Earth, Moon and Planets 10(1), 1750.


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Investigating nearby exoplanets via interstellar radar

  • Louis K. Scheffer (a1)


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