Lunar Delta-V Mission Planner
Build an educational lunar mission budget segment by segment. The tool combines your selected velocity changes with the Tsiolkovsky rocket equation so you can see how specific impulse and vehicle mass ratio affect ideal propulsion capability.
How to interpret the result
Delta-v is a convenient way to express the velocity-change capability a spacecraft must provide. It is not the same as distance travelled or maximum spacecraft speed. Each manoeuvre changes the vehicle's velocity vector, and the required value depends on the mission geometry.
The default segment values are deliberately editable illustrative assumptions. They are useful for understanding trade-offs, but they are not official requirements for every lunar mission. NASA mission-design studies show that lunar orbit insertion and end-to-end mission delta-v depend on launch date, trajectory geometry, target orbit, return constraints and broader mission architecture.
Rocket equation method
The calculator uses Δv = Isp × g0 × ln(m0/mf), where Isp is specific impulse in seconds, g0 is standard gravity, m0 is initial mass and mf is final mass after propellant expenditure. It assumes one effective specific impulse across the selected mission budget.
Important limitations
- The model treats manoeuvres as ideal impulsive velocity changes.
- It does not model finite-burn gravity losses, steering losses, boil-off, staging, attitude-control propellant or engine throttling.
- It does not design a safe trajectory or certify a spacecraft.
- Real mission reserves can be more complex than a single percentage margin.