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An orbital maneuver is a change from one orbit to another, accomplished by applying thrust. In deep space it is called deep-space maneuver (DSM).

An impulsive maneuver approximates a finite thrust maneuver by adding an instantaneous velocity change to an ephemeris record while maintaining the position. During the planning phase of most space or rocket missions, designers will first calculate orbital changes using impulsive maneuvers. This greatly reduces the complexity of finding the correct orbital transitions. The instantaneous changes in velocity are referred to as delta-v (), the total delta-v for all maneuvers required in the mission is called a delta-v budget. With a good approximation of the delta-v budget designers can estimate the fuel to payload requirements of the spacecraft. Using these approximations is most useful when finite thrusts are to be executed in short bursts. Finite maneuvers like these are possible with high thrust-to-weight propulsion systems, e.g. chemical rockets. However, even for long burns, impulsive maneuver approximations remain very accurate outside the Earth's atmosphere.

Applying a low thrust over longer periods of time is referred to as non-impulsive maneuvers (even though any thrust can be said to produce an amount of impulse). They are less efficient as energy can be lost due to gravity drag. However those maneuvers can be the only option when efficient but low thrust-to-weight propulsion systems are used (e.g. ion engines). They are not possible for a launch.

For a few space missions, such as those including a space rendezvous, high fidelity models of the trajectories are required to meet the mission goals. Calculating a finite burn requires a detailed model of the spacecraft and its thrusters. The most important of details include: mass, center of mass, moment of inertia, thruster positions, thrust vectors, thrust curves, specific impulse, thrust centroid offsets, and fuel consumption.

• Delta-v
• Delta-v budget
• Hohmann transfer
• Bi-elliptic transfer
• Docking maneuver
• Gravitational slingshot
• Orbital inclination change
• Orbit phasing

v • d • e  Orbits

Orbit types by characteristics: Box orbit | Circular orbit | Ecliptic orbit | Elliptic orbit | Highly Elliptical Orbit | Graveyard orbit | Hyperbolic trajectory | Inclined orbit | Osculating orbit | Parabolic trajectory | Capture orbit | Escape orbit | Semi-synchronous orbit | Subsynchronous orbit | Synchronous orbit Earth-centered orbits: Geosynchronous orbit | Geostationary orbit | Sun-synchronous orbit | Low Earth orbit | Medium Earth Orbit | Molniya orbit | Near equatorial orbit | Orbit of the Moon | Polar orbit | Polar sun synchronous orbit | Tundra orbit Orbits about other bodies: Areosynchronous orbit | Areostationary orbit | Lunar orbit | Heliocentric orbit | Heliosynchronous orbit Orbital elements: Inclination () | Longitude of the ascending node () | Eccentricity () | Argument of periapsis () | Semimajor axis () | Mean anomaly at epoch () Other orbital parameters: True anomaly () | Semi-major axis () | Semi-minor axis () | Linear eccentricity () | Eccentric anomaly () | Mean longitude () | True longitude () | Orbital period () Orbital maneuvers: Bi-elliptic transfer | Geostationary transfer orbit | Gravitational slingshot | Hohmann transfer orbit | Orbital inclination change | Orbit phasing | Space rendezvous Other orbital mechanics topics: Apsis | Celestial coordinate system | Delta-v budget | Epoch | Ephemeris | Equatorial coordinate system | Ground track | Interplanetary Transport Network | Kepler's laws of planetary motion | Lagrangian point | List of orbits | n-body problem | Orbit equation | Orbital state vectors | Retrograde and direct motion | Specific orbital energy | Specific relative angular momentum