Online pork-chop plotting application

The present application provides an extremely efficient (although approximate) solution of the Lambert's Targeting Problem (LTP) to produce launch and arrival v-infinity pork-chop plots between solar system targets selected by the user. The solution method is based on the works:

  • Approximate Analytical Solution of the Lambert's Targeting Problem. Claudio Bombardelli, Juan Luis Gonzalo, Javier Roa. In Journal of Guidance, Control and Dynamics, Volume 41, Issue 3, 2018, pp. 792-801. https://doi.org/10.2514/1.G002887.
  • Approximate Analytical Solution of the Lambert's Targeting Problem. Claudio Bombardelli, Javier Roa, Juan Luis Gonzalo. Paper AAS 16-212 in 26th AAS/AIAA Space Flight Mechanics Meeting, Napa, CA, USA, 14-18 February 2016.

Solar system bodies move on Keplerian orbits (all perturbations are neglected) and transfer arcs are Keplerian.

Warning: errors of up to 15-20% may appear in the computation of very inefficient transfer arcs (i.e. far from minimum delta-V conditions).
Remember to select a sufficiently long transfer time in order to obtain meaningful trajectories.

The application is quite straightforward to use. Choose ranges for the departure date and time of flight, set the ephemeris for your departure and arrival bodies (a list with several planets and asteroids is also available), and click on one of the compute buttons for departure or arrival v-infinity. You can interact with the resulting contour plots by clicking on the colorbar to change the displayed levels, or placing the pointer over them to get a data cursor.

Departure Date
- -
- -
Time of Flight
Departure body
Arrival body
Departure V-infinity
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Arrival V-infinity
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Copyright 2016-2019 Juan Luis Gonzalo, Universidad Politécnica de Madrid (Technical University of Madrid).
This program is distributed as free software under the GPLv3 or later. For more information see the COPYING file.
This webpage uses minified versions of the Javascript code for efficiency. The full code, together with a sample HTML file, can be downloaded here.


  • The plotting functionality is based on the HTML5 canvas. An HTML5-compliant browser is required (this excludes Internet Explorer 8 and earlier).
  • MarchingSquaresJS, a Javascript implementation of the marching squares algorithm by Ronny Lorenz, is used for isoband computation. See the MarchingSquaresJS GitHub project for the full code and detailed information on licensing (under the AGPL v3).
  • The underlying JavaScript code makes use of mathematical functions in the 6th edition of the ECMA-262 standard (June 2015). Polyfills have been included for the most recent functions (such as atanh), but compatibility (or performance) is not guaranteed for older browsers.