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The challenge of the exploded planet hypothesis

  • Tom Van Flandern (a1)

The hypothesis of the explosion of a number of planets and moons of our Solar System during its 4.6-billion-year history is in excellent accord with all known observational constraints, even without adjustable parameters or ad hoc helper hypotheses. Many of its boldest predictions have been fulfilled. In most instances, these predictions were judged highly unlikely by the current standard models. Moreover, in several cases, the entire exploded planet model was at risk of being falsified if the predictions failed. The successful predictions include: (1) satellites of asteroids; (2) satellites of comets; (3) salt water in meteorites; (4) ‘roll marks’ leading to boulders on asteroids; (5) the time and peak rate of the 1999 Leonid meteor storm; (6) explosion signatures for asteroids; (7) the strongly spiked energy parameter for new comets; (8) the distribution of black material on slowly rotating airless bodies; (9) splitting velocities of comets; (10) the asteroid-like nature of Deep Impact target Comet Tempel 1; and (11) the presence of high-formation-temperature minerals in the Stardust comet dust sample return. In physics and astronomy, hypotheses are either falsified if their predictions fail, or proved to be of value if they succeed. By all existing evidence, the exploded planet hypothesis has proved far more useful than the half-dozen or so hypotheses it would replace. Among the many important corollaries are these. (a) Perhaps as many as six former planets of our Solar System have exploded over its 4.6-billion-year history. (b) In particular, Mars is not an original planet, but a former moon of an exploded planet. (c) As a major player in Solar System evolution, the exploded planet scenario must be considered as a likely propagation vehicle for the spread of biogenic organisms. We conclude with a brief mention of three possible planetary explosion mechanisms.

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Binzel, R.P. & Van Flandern, T.C. (1979). Minor planets: the discovery of minor satellites. Science 203, 903905.
Christiansen, E.H. & Hamblin, W.K. (1995). Exploring the Planets, 2nd edn, p. 144. Prentice-Hall, Englewood Cliffs, NJ.
Clayton, R.N. (1999). Primordial water. Science 285, 13641365 & 13771379.
Cohen, B.A., Hewins, R.H. & Yu, Y. (2000). Evaporation in the young solar nebula as the origin of ‘just-right’ melting of chondrules. Nature 406, 600602.
Cowen, R. (1997). A moon for Dionysus. Sci. News 152, 200.
Harrington, R.S. & Van Flandern, T.C. (1979). The satellites of Neptune and the origin of Pluto. Icarus 39, 131136.
Herndon, J.M. (1998). Examining the overlooked implications of natural nuclear reactors. Eos (Transact. Amer. Geophys. Union) 79, 451 & 456; see also and
Hoyle, F. & Wickramasinghe, N.C. (1979). Diseases from Space. Dent, London.
Jewett, D.L. (2007). The conceptual benefits of ‘exploding planets’ as a mechanism for Panspermia. (in process).
Jones, D.C., Williams, I.P. & Melita, M.D. (2005). The dynamics of objects in the inner Edgeworth–Kuiper belt. Earth, Moon & Planets 97, 435458.
Kerr, R.A. (1999). Asteroids form rocky relationships. Science 284, 10991101.
LeDuin, T., Levasseur-Rigourd, A.C. & Renard, J.B. (1993). Dust and gas brightness profiles in the Grigg–Skjellerup coma from OPE/Giotto. In Abstracts for IAU Symposium 160: Asteroids, Comets, Meteors, Belgirate (Navara), Italy, 1991, p. 182. Lunar & Planetary Institute, Houston, TK.
Liffman, K. (1992). The formation of chondrules via ablation. Icarus 100, 608620.
Lipton, P. (2005). Testing hypotheses: prediction and prejudice. Science 307, 219.
Littmann, M. (1988). Planets Beyond, 1922. Wiley Science Editions, New York.
Lyytinen, E. (1999). Leonid predictions for the years 1999–2007 with the satellite model of comets. Meta Res. Bull. 8, 3340.
Lyytinen, E. & Van Flandern, T. (2004). Perseid one-revolution outburst in 2004. WGN (J. of Int'l. Meteor Org.) 32, 2 & 5153.
Marchis, E., Bochnhardt, H., Hainaut, O.R. & Le Mignant, D. (1999). Adaptive optics observations of the innermost coma of C/1995 O1: are there a ‘Hale’ and a ‘Bopp’ in comet Hale–Bopp? Astron. Astrophys. 349, 985995.
Miles, K.A. & Peters, C.F. II (1997). Origins of the asteroids.
Newcomb, S. (1860). On the Secular Variations and Mutual Relations of the Orbits of the Asteroids, Memoirs of the American Academy of Arts and Sciences 5, 123152.
Opik, E.J. (1978). The missing planet. Moon and the Planets 18, 327337.
Ramsey, W.H. (1950). On the instability of small planetary cores (I). Mon. Not. R. Astron. Soc. 110, 325338.
Schultz, P.H. & Posin, S. (1988). Global catastrophes in Earth history. LPI Contrib. 673, 168169.
Sekanina, Z. (1982). The problem of split comets in review. Comets, pp. 251287. University of Arizona Press, Tucson, AZ.
Sekanina, Z. (1997). Detection of a satellite orbiting the nucleus of Comet Hale–Bopp (C/1995 O1). Earth, Moon & Planets 77, 155163.
Taylor, G.J. & Heymann, D. (1969). Shock, reheating, and the gas retention ages of chondrites. Earth Planet. Sci. Lett. 7, 151161.
Van Flandern, T. (1978). A former asteroidal planet as the origin of comets. Icarus 36, 5174.
Van Flandern, T. (1981). Do comets have satellites? Icarus 47, 480486.
Van Flandern, T. (1992). Minor satellites and the Gaspra encounter. In Proceedings of Asteroids, Comets, Meteors, Lunar & Planetary Institute, Houston, 1991, pp. 609612.
Van Flandern, T. (1993). Dark Matter, Missing Planets and New Comets, pp. 215236, 178. North Atlantic Books, Berkeley, CA (2nd edn 1999).
Van Flandern, T. (1996). Possible new properties of gravity. Astrophys. Space Sci. 244, 249261.
Van Flandern, T. (1997a). Comet Hale–Bopp update. Meta Res. Bull. 6, 2932.
Van Flandern, T. (1997b). The original Solar System. Meta Res. Bull. 6, 1729; see also <>.
Van Flandern, T. (1999a). Status of ‘the NEAR challenge’. Meta Res. Bull. 8, 3132. Also available at <>.
Van Flandern, T. (1999b). 1999 Leonid meteor storm – how the predictions fared. Meta Res. Bull. 8 5963.
Van Flandern, T. (2002). What really happened at the K/T extinction event. Meta Res. Bull. 11, 14.
Van Flandern, T. (2005a). Deep Impact: coming clues to the origin of the Solar System. Meta Res. Bull. 14, 1723; see also <>, posted 1st May 2005.
Van Flandern, T. (2005b). Deep Impact probe hits Comet Tempel 1. Meta Res. Bull. 14, 3338; see also
Van Flandern, T.C. & Harrington, R.S. (1976). A dynamical investigation of the conjecture that Mercury is an escaped satellite of Venus. Icarus 28, 435440.
Weissman, P.R. (1989). The impact history of the Solar System: implications for the origin of atmospheres. In Origin and Evolution of Planetary and Satellite Atmospheres, eds Atreya, S.K., Pollack, J.B. & Matthews, M.S., pp. 247249. University of Arizona Press, Tucson, AZ.
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International Journal of Astrobiology
  • ISSN: 1473-5504
  • EISSN: 1475-3006
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