John R. Thorstensen

Academic Appointments
  • Professor of Physics and Astronomy

  • President, MDM Observatory Corporation

John Thorstensen is an optical observational astronomer. He has been at Dartmouth since 1980. His undergraduate degree was from Haverford College (1974), which was followed by graduate studies in the Berkeley (California) Astronomy Department. He specializes in observations of cataclysmic binary stars. Since 2007 he has served as the director of the MDM Observatory on Kitt Peak, Arizona; MDM is operated by a consortium of five universities. Thorstensen developed the program JSkyCalc and its antecedents, which are widely used in planning observations.

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239 Wilder
HB 6127


  • B.A. Haverford College
  • Ph.D. University of California at Berkeley

Selected Publications

  • Thorstensen, J. R. Ringwald, F. A.,  Taylor, C. J., Sheets, H. A., Peters, C. S., Skinner, J. N., Alper, E. H., and Weil, K. E. 2017, "New or Improved Orbital Periods of Cataclysmic Binaries", 2017, Research Notes of the AAS, 1, 29.  Available at

  • Thorstensen, J. R., Alper, E. H., and Weil, K. E. 2016,  "A Trip to the Cataclysmic Binary Zoo: Detailed Follow-Up of 35 Recently-Discovered Systems'',  The Astronomical Journal, 152, 226.  Preprint version at arXiv:1609.02215

  • Halpern, J. P., and Thorstensen, J. R. 2015, "Optical Studies of Thirteen Hard X-ray Selected Cataclysmic Binaries",  Astronomical Journal, 150, 170. Available at arXiv:1510.00703

  • Skinner, J. N., Thorstensen, J. R., and Lepine, S. 2014, "Cataclysmic Variables in the SUPERBLINK Proper Motion Survey", Astronomical Journal, 148, 115.  Available at arXiv:1409.1921

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Works In Progress

  • Thorstensen has many observations of cataclysmic binaries, most importantly orbital periods, that have not yet been published in detail; the RNAAS reference in the publications list includes many, but not all of these.  Queries from interested observers are encouraged. 

  • A ground-based parallax program has been suspended, because of the expected publication of the GAIA parallax and proper motion catalog in 2018.