SpaceX Starship Vehicle

The shape of SpaceX Starship vehicle’s front fins cannot be approximated by any Geant4 CSGs due to the tapering of the vehicle’s body toward its tip. This can be solved by embeding part of a trapezoid into the vehicle’s body through the UNION operation of two CSGs, a trapezoid approximating the fin and a series of polycone approcimating the body.

The geometry is defined in vehicle.tg. Dimensions are measured using an on-screen ruler on drawings from https://forum.nasaspaceflight.com/index.php?topic=50049.0. Fire out of the vehicle is mimicked using many electrons, as demonstrated in gears.mac. The animation shown on YouTube is generated using tsg.mac and loop.mac.