Community Resources

Please email if interested in something that is not linked online yet.
Updated December 21, 2011.


  1. Analytic collision outcome model
  2. Tabular equations of state
  3. Constitutive models for the shock code CTH
  4. Data from Lonar crater, India
    • Quickbird image, digital elevation map, ASTER images, hand samples
  5. Martian craters
    • Measurements database, simulated craters, HMars
  6. Shock wave technical databases and resources
  • Analytic collision outcome model

    Zoe Leinhardt and I have developed an analytic model to predict the outcome of any collision between gravity-dominated bodies.

          New: Online 'Planetary Collision Calculator'

    In addition, here is an IDL program to calculate collision outcomes and make collision outcome maps: (fixing bugs in IDL code - check back soon) and IDL data file for velocity probability scaling. We also present a more detailed derivation of the model and comparisons and fits to numerical simulation results from various studies: derivation.pdf.

    Online calculators for impact cratering:
    Crater size and ejecta (Holsapple, Housen, & Narayan)
    Crater size (Melosh & Beyer)
    Environmental effects & crater size (Marcus, Melosh, & Collins)

  • Equations of State

    We have the following tabulated (Sandia SESAME-style) equations of state:

    1. The 5-Phase H2O tabular equation of state, which is described in the appendix of Senft and Stewart MAPS 2008. The EOS includes ice Ih, ice VI, ice VII, liquid, and vapor in a high resolution density-temperature grid. (Distribution notes PDF)
    2. A high resolution table of the M-ANEOS SiO2 model from Melosh, H. J., A hydrocode equation of state for SiO2, Meteoritics and Planetary Science, 42, 2079-2098, 2007.
    3. A high resolution table of the M-ANEOS Forsterite model from Melosh.

    Please register as a user of our equation of state tables to receive corrections, updates, and information about new tables. Send your contact information to Sarah to receive copies of current tables.

    See also equation of state tutorials and EOSPro software package by Gerald Kerley.

  • Constitutive Models for CTH

    The citation for the following routines is Senft and Stewart JGR 2007 (which describes the implementation and tests):
    1. The quasi-static strength model of Collins, G. S., H. J. Melosh, and B. A. Ivanov, Modeling damage and deformation in impact simulations, Meteoritics and Planetary Science, 39, 217-231, 2004.
    2. The Bingham fluid approximation for acoustic fluidization based on the implementation in iSALE by Gareth Collins, Kai Wuennemann, and colleagues.

    These routines will be distributed with future versions (v10) of CTH. Please also register as a user of our CTH routines to receive corrections, updates, and information about new functions. Send your contact information to Sarah.

  • Lonar crater, India

    1. A 4-band (RGB+NIR) pan-sharpened (0.6 m resolution) Quickbird GeoTIFF of Lonar crater. This image was commissioned as part of the field work presented in Maloof et al., GSA Bull., 2010, and this publication should be cited as the source. Email for ftp download information for the full data set (4.7 Gb). Full resolution jpeg images (60 Mb each): RGB and (NIR)GB (note that some browsers have trouble with these large images).
    2. A digital elevation map of Lonar crater derived from hand-held GPS. The DEM is published in the data repository with Maloof et al., GSA Bull., 2010. Download the Lonar DEM zip file - 13 Mb.
    3. ASTER satellite image of Lonar. Email for ftp download information (120 Mb).
    4. Hand samples, paleomag cores, and spherules from Lonar crater. Email for spreadsheet.

  • Martian craters

    1. Crater geometric measurements database from Valiant and Stewart, MAPS, 2006 and Black and Stewart, JGR, 2008. Download the zip file.
    2. Simulated craters data set for testing crater geometry measurement techniques. The data set includes simulated MOLA tracks of craters with prescribed geometries on different background terrains. Cite Valiant and Stewart, MAPS, 2006. Email for ftp download information (2.4 Gb).
    3. The HMars interactive interface for MOLA and imagery data, which is described in Valiant and Stewart, MAPS, 2006. This set of IDL routines was specifically developed to measure the volumes of craters and ejecta blankets. The JMARS toolkit is a much more versatile interface to current Martian data sets.

  • Shock wave and impact cratering technical databases and resources

    Here are some pointers to sources of shock wave data:
    1. Thomas J. Ahrens publications archive.
    2. AGU Reference Shelf: compilation of rock and mineral Hugoniot data.
    Ahrens, T. J., and M. L. Johnson (1995), Shock Wave Data for Minerals, in Mineral Physics and Crystallography, A Handbook of Physical Constants, Vol. 2, edited by T. J. Ahrens, pp. 143-184, Amer. Geophys. Union., Washington, D.C. (PDF) (Google book)
    Ahrens, T. J., and M. L. Johnson (1995), Shock Wave Data for Rocks, in Rock Physics and Phase Relations, A Handbook of Physical Constants, Vol. 3,, edited by T. J. Ahrens, pp. 35-44, Amer. Geophys. Union, Washington, D.C. (PDF) (Google Book)
    3. Marsh, S. P. (Ed.) (1980), LASL Shock Hugoniot Data, U. California Press, Berkeley.
          Google book and ZIP file of the data.
    4. Russian shock wave database (
    5. Impact and explosion craters database and scaling tools from Keith Holsapple and Kevin Housen.
    6. Crater scaling program from Melosh and Beyer.
    7. Planetary Crater Consortium
    8. The impact code validation and benchmark project.
    9. Search US technical reports (gray literature) at
    10. U. Cambridge Cavendish Laboratory bibliographies.
    11. Proceedings of the biennial Shock Compression of Condensed Matter meeting (search AIP conference proceedings).
    12. Gerald Kerley's web site: Equation of state tutorials and his EOSPro code.
    13. Shock wave and ballistics facilities.

Sarah T. Stewart-Mukhopadhyay
Department of Earth and Planetary Sciences
Harvard University
20 Oxford Street
Cambridge, MA 02138

Google Voice: 617.863.0423
Fax: 617.384.8249
Email: sstewart (at)