jump Index ScientificPsychic.com
Scientific Psychic

Calculate Crater size from Projectile Diameter

This program estimates the size of a gravity-dominated impact crater made by a projectile whose attributes are known. Three different estimates are presented, but the Pi-scaling method is currently considered the best.
(See also the Projectile Size calculator)

Projectile Descriptors

Enter the projectile diameter in meters

Enter the projectile density in kg/m3


Impact Conditions

Enter the impact velocity in km/sec


Enter the impact angle in degrees

The impact angle is measured between the approach trajectory and a plane tangent to the surface. This angle is 90 degrees for a vertical impact.

Target Descriptors

Enter the target density in kg/m3


Enter the acceleration of gravity in m/sec2

Target Type
liquid water
loose sand
competent rock or saturated soil

Calculate Projectile Size from Crater Diameter

The program is based on a FORTRAN 77 program originally written by Prof. H. Jay Melosh and converted to Perl by Ross A. Beyer. More information about the equations can be found in the book by Melosh: Impact Cratering: A Geologic Process, Oxford University Press, 1989, or in the related publication, below.

This program was originally hosted at the Lunar & Planetary Laboratory of the University of Arizona. The files were removed when Prof. Melosh transferred to Purdue University. The HTML file was archived on 3:28:10 Jan 11, 2016 and retrieved from the Internet archive on 22:27:34 Feb 4, 2016. The program is free software under the terms of the GNU General Public License.

Related Publication:
Gareth S. Collins, H. Jay Melosh and Robert A. Marcus, Earth Impact Effects Program: A Web-based computer program for calculating the regional environmental consequences of a meteoroid impact on Earth, Meteoritics & Planetary Science 40, Nr 6, 817–840 (2005). PDF

© Copyright  - Antonio Zamora