A transfer window is the brief period when the orbital positions of two celestial bodies align perfectly for a spacecraft to travel between them. Launching during this period allows the vehicle to use an efficient trajectory, requiring the lowest possible change in velocity. Missing this alignment forces a mission to wait months or years for the planets to move back into the correct geometric relationship.
We've a three-week transfer window for the Mars shot before the delta-v requirements exceed our fuel budget.
Do not mix it up with
- Launch window: A launch window is the specific time of day a rocket can leave Earth to reach a target orbit, while a transfer window dictates the days or weeks when planetary bodies are aligned for an interplanetary trip.
Related terms
Launch window
The specific timeframe during which a spacecraft must lift off to reach its intended orbit or target.
Delta-v
The total change in velocity a spacecraft can achieve using its available propellant.
Trajectory
The three-dimensional flight path of an aircraft, rocket, or spacecraft.
Rendezvous
A series of orbital maneuvers that bring two spacecraft into close proximity.