What do Porkchops and Mars Missions Have To Do With Each Other?

The launch window for Mars is open, and we have 3 spacecraft headed for the red planet from 3 different countries, and performing 3 very different missions. Let's talk about these missions, and since I was asked on twitter, I'm going to explain how mission planners pick launch dates using 'Pork Chop Plots'

JPL Trejctory Browser
https://trajbrowser.arc.nasa.gov/traj_browser.php

On The Nature Of Porkchop Plots
https://pdfs.semanticscholar.org/ffbe/ce81839847de08ea7712aa289962018363e8.pdf

Easy Porkchop Plot
http://sdg.aero.upm.es/index.php/online-apps/porkchop-plot

Видео What do Porkchops and Mars Missions Have To Do With Each Other? канала Scott Manley