Enter the semi-major axis, eccentricity, true anomaly, and true anomaly at the periapsis into the calculator to determine the transfer window time.

Ksp Transfer Window Formula

The following formula is used to calculate the transfer window for interplanetary travel in Kerbal Space Program (KSP).

TW = (A * (1 - e^2) / (2 * e)) * sin(2 * (θ - θ0))


  • TW is the transfer window time (seconds) A is the semi-major axis of the transfer orbit (meters) e is the eccentricity of the transfer orbit (dimensionless) θ is the true anomaly (radians) θ0 is the true anomaly at the periapsis (radians)

To calculate the transfer window, first subtract the square of the eccentricity from 1 and multiply the result by the semi-major axis. Divide this by twice the eccentricity. Then, subtract the true anomaly at the periapsis from the true anomaly and double the result. Take the sine of this and multiply it by the first result to get the transfer window time.

What is a Ksp Transfer Window?

A Ksp (Kerbal Space Program) Transfer Window is a specific time period in which a spacecraft can be launched to ensure the most efficient path to its destination. This window is calculated based on the relative positions of the planets and their orbits. The transfer window minimizes the amount of fuel and time required to reach the target destination. It is a critical aspect of space mission planning in both real-world space exploration and in the Kerbal Space Program game.