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Zdenek Sekanina

Photo of Zdenek Sekanina

Address:

4800 Oak Grove Drive
M/S 183-501 Pasadena, CA 91109

Phone:

818.354.7589

Fax:

818.354.0966

Member of:

Small Bodies

Education

  • B.S. in Astronomy (with honors), Charles University, Praha, Czechoslovakia (1959)
  • RNDr. in Astronomy, Charles University, Praha, Czechoslovakia (1963)
  • Ph.D. in Astronomy, Charles University, Praha, Czechoslovakia (1963)

Professional Experience

  • Jet Propulsion Laboratory (1980-present)
    • IEP, Earth and Space Sciences Division (2010-present)
    • Principal Scientist, Earth and Space Sciences Division (1999-2010)
    • Senior Research Scientist, Earth and Space Sciences Division (1984-2010)
    • Research Scientist, Earth and Space Sciences Division (1981-1984)
    • Member, Technical Staff, Earth and Space Sciences Division (1980-1981)
  • Visiting Scientist, European Southern Observatory, Garching bei Munchen, Germany (1997)
  • Physicist, Smithsonian Astrophysical Observatory (1969-1980)
  • Associate Director, Central Bureau for Astronomical Telegrams, International Astronomical Union (1970-1980)
  • Associate, Harvard College Observatory (1970-1980)
  • Visiting Scientist, Institut d' Astrophysique, Universite de Liege, Cointe-Ougree, Belgium (1965, 1968-1969)
  • Scientific Collaborator, Center for Numerical Mathematics, Faculty of Mathematics and Physics, Charles University, Praha, Czechoslovakia (1967-1968)
  • Visiting Scientist, Hamburger Sternwarte, Hamburg-Bergedorf, Germany (1966)
  • Astronomer, Stefanik Observatory, Prague, Czechoslovakia (1959-1966)

Research Interests

  • Physics, evolution, and dynamics of comets
  • Physics and dynamics of meteors and fireballs
  • Physics and dynamics of interplanetary matter

Selected Awards

  • Frantisek Nusl Prize by the Czech Astronomical Society (2006)
  • NASA Exceptional Achievement Medal (2005)
  • NASA Group Achievement Award, Stardust Flight Team (2005)
  • NASA/JPL Certificate of Recognition (Stardust Mission) (2004)
  • NASA Group Achievement Award, Stardust Camera Anomaly Team (2002)
  • Elected honorary member of the Czech Astronomical Society (2001)
  • Elected honorary (foreign) member of the Learned Society of the Czech Republic (equivalent to U.S. National Academy) (1996)
  • NASA Exceptional Scientific Achievement Medal (1985)
  • Outstanding Scientific Performance Certificate, Smithsonian Astrophysical Observatory (1980)
  • Minor Planet No. 1913 named Sekanina, lvIinor Planet Center, International Astronomical Union (1976)

Selected Publications

  1. Keane, J. V., Milam, S. N., Coulson, I. M., Kleyna, J. T., Sekanina, Z., Kracht, R., Riesen, T.-E., and Charnley, S. B., Catastrophic Disruption of Comet ISON. Astrophys. J. 831, 207 (7pp), 2016.
  2. Sekanina, Z., and Kracht, R., Pairs and Groups of Genetically Related Long-Period Comets and Proposed Identity of the Mysterious Lick Object of 1921. J. 823, 2 (26pp), 2016.
  3. Sekanina, Z., and Kracht, R., Was Comet C/1945 X1 (du Toit) a Dwarf, SOHO-Like Kreutz Sungrazer? J. 815, 52 (22pp), 2015.
  4. Sekanina, Z., and Kracht, R., Strong Erosion-Driven Nongravitational Effects in Orbital Motions of the Kreutz Sungrazing System's Dwarf Comets. J. 801, 135 (19pp), 2015.
  5. Sekanina, Z., and Kracht, R., Population of SOHO/STEREO Kreutz Sungrazers and the Arrival of Comet C/2011 W3 (Lovejoy). J. 778, 24 (13pp), 2013.
  6. Sekanina, Z., and Chodas, P. W., Comet C/2011 W3 (Lovejoy): Orbit Determination, Outbursts, Disintegration of Nucleus, Dust-Tail Morphology, and Relationship to New Cluster of Bright Sungrazers. J. 757, 127 (33pp), 2012.
  7. Sekanina, Z., Outbursts and Fragmentation of Comet 168P. Comet Quart. 32, 45-70, 2010.
  8. Sekanina, Z., Recurrence of Super-Massive Explosions and Orbital Evolution of Comet 17P/Holmes. II. Search for Historical Records, and Outlook for Future Research. Comet Quart. 32, 3-32, 2010.
  9. Sekanina, Z., Crystallization of Gas-Laden Amorphous Water Ice, Activated by Heat Transport to Its Subsurface Reservoirs, As Trigger of Huge Explosions of Comet 17P/Holmes. Comet Quart. 31, 99-124, 2009.
  10. Sekanina, Z., Recurrence of Super-Massive Explosions and Orbital Evolution of Comet 17P/Holmes. I. Missed 1913-1957 Returns to the Sun. Comet Quart. 31, 45-65, 2009.
  11. Sekanina, Z., Comet 17P/Holmes: A Megaburst Survivor. Comet Quart. 31, 5-23, 2009.
  12. Sekanina, Z., and Chodas, P. W., A New Orbit Determination for Bright Sungrazing Comet of 1843. J. 687, 1415-1422, 2008.
  13. Sekanina, Z., Episodic Aging and End States of Comets. In Instruments, Methods,and Missions for Astrobiology XI, ed. R. B. Hoover, G. V. Levin, A. Y. Rozanov,and P. C. Davies, Proceedings of the SPIE, vol. 7097, 70970X, 15pp, 2008.
  14. Sekanina, Z., On a Forgotten 1836 Explosion from Halley's Comet, Reminiscent of 17P/Holmes' Outbursts. Comet Quart. 30, 63-74, 2008.
  15. Sekanina, Z., Exploding Comet 17P/Holmes. Comet Quart. 30, 3-28, 2008.
  16. Sekanina, Z., Dust Jets, Outbursts, and Fragmentation of Comets. In Instruments, Methods, and Missions for Astrobiology X, ed. R. B. Hoover, G. V. Levin, A. Y.Rozanov, and P. C. W. Davies, Proceedings of the SPIE, vol. 6694, 66940I, 2007.
  17. Sekanina, Z., and Chodas, P. W., Fragmentation Hierarchy of Bright Sungrazing Comets and the Birth and orbital Evolution of the Kreutz System. II. The Case for Cascading Fragmentation. J. 663, 657-676, 2007.
  18. Sekanina, Z., Earth's 2006 Enclounet with Comet 73P/Schwassmann-Wachmann: Products of Nucleus Frgamentation Seen in Closeup. In Near-Earth Objects, Our Celestial Neighbors: Opportunity and Risk, Proceedings of IAU Symposium 236, ed. G. B. Valsecchi, D. Vokrouhlicky, and A. Milani (Cambridge, UK: Cambridge Univ. Press), 211-220, 2007.
  19. Sekanina, Z., and P. W. Chodas, Origin of the Marsden and Kracht Groups of Sunskirting Comets. I. Association with Comet 96P/Machholz and Its Interplanetary Complex. J. Suppl. Ser. 161, 551-586, 2005.
  20. Sekanina, Z., Comet 73P/Schwassmann-Wachmann: Nucleus Fragmentation, Its Light-Curve Signature, and Close Approach to Earth in 2006. Comet Quart. 27, 225-240, 2005.
  21. Sekanina, Z., D. E. Brownlee, T. E. Economou, A. J. Tuzzolino, and S. F. Green, Modeling the Nucleus and Jets of Comet 81P/Wild 2 Based on the Stardust Encounter Data. Science 304, 1769-1774, 2004.
  22. Sekanina, Z., and P. W. Chodas, Fragmentation Hierarchy of Bright Sungrazing Comets and the Birth and Orbital Evolution of the Kreutz System. I. Two-Superfragment Model. J. 607, 620-639, 2004.
  23. Sekanina, Z., Erosion Model for the Sungrazing Comets Observed with the Solar and Hcliospheric Observatory. J. 597, 1237-1265, 2003.
  24. Sekanina, Z., A Model for Comet 81P/Wild 2. Geophys. Res. 108, E10, 8112, 2003.
  25. Sekanina, Z., P. W. Chodas, M. Tichy, J. Ticha, and M. Kocer, Peculiar Pair of Distant Periodic Comets C/2002 A1 and C/2002 A2 (LINEAR). J. 591, L67-L70, 2003.
  26. Sekanina, Z., Statistical Investigation and Modeling of Sungrazing Comets Discovered With the Solar and Heliospheric Observatory. J. 566, 577-598, 2002.
  27. Sekanina, Z., E. Jehin, H. Boehnhardt, X. Bonfils, O. Schuetz, and D. Thomas, Recurring Outbursts and Nuclear Fragmentation of Comet C/2001 A2 (LINEAR). J. 572, 679-684, 2002.
  28. Sekanina, Z., Runaway Fragmentation of Sungazing Comets Observed With the Solar and Heliospheric Observatory. J. 576, 1085-1089, 2002.
  29. Sekanina, Z., and P. W. Chodas, Common Origin of Two Major Sungrazing Comets. J. 581, 760-769, 2002.
  30. Sekanina, Z., M. S. Hanner, E. K. Jessberger, and M. N. Fomenkova, Cometary Dust. In: Interplanetary Dust, E. Grun, B. A. S. Gustafson, S. F. Dermott, and H. Fechtig, Eds., Springer, Heidelberg, Germany, pp. 95-161, 2001.
  31. Sekanina, Z., and H. Boehnhardt, Dust Morphology of Comet Hale-Bopp (C/1995 O1). II. Introduction of a Working Model. Earth Moon Plan. 78, 313-319, 1999.
  32. Sekanina, Z., Detection of a Satellite Orbiting the Nucleus of Comet Hale-Bopp (C/1995 O1). Earth Moon Plan. 77, 155-163, 1999.
  33. Sekanina, Z., Evidence for Asteroidal Origin of the Tunguska Object. Space Sci. 46, 191-204, 1998.
  34. Sekanina, Z., P. W. Chodas, and D. K. Yeomans, Secondary Fragmentation of Comet Shoemaker-Levy 9 and the Ramifications for the Progenitor's Breakup in July 1992. Space Sci. 46, 21-45, 1998.
  35. Sekanina, Z., Modeling the Diurnal Evolution of a Dust Feature in Comet Hale-Bopp (1995 O1). J. 494, L121-L124, 1998