Algodoo

NEON thrust system is ASP-valid and operates similar to Ion thrusters, but is more powerful.
the fuel, which is transparent and has a refractive index of 1, is pulled by the gravity of two dark pink circles into the engine.
Upon hitting a laser, the fuel particles can now collide with layer I, which causes them to be repelled by the lime circle above the laser. This pushes the whole rocket up with more than enough force to hover in standard gravity. Like the V2 rocket accelaration system, this also removes any spent fuel over age 1 second. even better than ion propulsion, is the fact that the two lime circles at the bottom also repel the fuel when the horizontal arrow keys are pressed, making the thruster vectorable!