Your spacecraft. Your trajectory. One extraordinary journey.
Choose a mission, adjust the labeled controls, then press Play. Reset restarts the current configuration. Vehicle edits remain a draft until Apply configuration & restart; throttle and guidance controls can act during flight. Transfer missions require Execute Transfer. Share a mission using the links below; links open its default setup, not a saved flight.
a = −μr / |r|³. μ = GM is the body’s gravitational parameter; r is spacecraft position relative to that body. Accelerations from the selected bodies are added.v_circular = √(μ/r); v_escape = √(2μ/r). Here r is distance from the body’s center, not altitude. A spacecraft below escape speed can remain in orbit; impact depends on its full trajectory.Δv = Isp g₀ ln(m₀/m_f). Isp is specific impulse in seconds, g₀ is standard gravity, and m₀ and m_f are initial and final mass. Ideal Δv excludes gravity and drag losses.ṁ = F/(Isp g₀). F is thrust and ṁ is propellant consumption in kg/s. Lift-off requires sufficient upward thrust relative to weight.D = ½ρv_air² C_D A. Density ρ falls exponentially with altitude; v_air is air-relative speed, C_D is drag coefficient and A is frontal area.This educational model uses two-dimensional motion, RK4 integration and prescribed circular planetary orbits. Capture burns are idealized impulses. The guided launch cuts off at the target apoapsis, circularizes with a fuel-accounted idealized impulse, then waits for lunar departure alignment. Lunar capture is checked for binding energy and surface clearance. Mars mode starts after conceptual Earth escape and omits Earth’s gravity during heliocentric coast. There is no seamless launch-to-Mars campaign, detailed aerodynamics, heating or structural simulation. Globe terrain is procedural, not geographic survey data; lighting is illustrative. Flight dynamics remain two-dimensional. Vehicle visuals are illustrative; a component/shape editor is not included in this version.