Delta-V & Hohmann Transfer — built while learning in public
What is Δv? (Click to expand)▼
Δv (delta-v) is the total change in velocity your rocket can produce with its onboard fuel.
It is the single most important number in spaceflight. No matter how powerful your engine is, if you don’t have enough Δv you simply can’t reach your destination.
This calculator uses the Tsiolkovsky rocket equation to show you how much Δv you get from a given amount of fuel.
What is a Hohmann Transfer? (Click to expand)▼
A Hohmann Transfer is the most fuel-efficient way to travel between two circular orbits.
It works by burning once to enter an elliptical “transfer orbit”, coasting halfway around, then burning again to circularize at the target orbit.
Almost every satellite going from Low Earth Orbit to Geostationary Orbit uses a Hohmann transfer.