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Encyclopedia > Orbital maneuver

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). Two bodies with a slight difference in mass orbiting around a common barycenter. ... Thrust is a reaction force described quantitatively by Newtons Second and Third Laws. ...

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Impulsive maneuvers

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 (Deltamathbf{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. General In general physics delta-v is simply the change in velocity. ... General In general physics delta-v is simply the change in velocity. ... Delta-v budget (or velocity change budget) is a term used in astrodynamics and aerospace industry for velocity change (or delta-v) requirements for the various propulsive tasks and orbital maneuvers over phases of the space mission. ... Delta-v budget (or velocity change budget) is a term used in astrodynamics and aerospace industry for velocity change (or delta-v) requirements for the various propulsive tasks and orbital maneuvers over phases of the space mission. ... Thrust is a reaction force described quantitatively by Newtons Second and Third Laws. ... A remote camera captures a close-up view of a Space Shuttle Main Engine during a test firing at the John C. Stennis Space Center in Hancock County, Mississippi Propulsion means to add speed or acceleration to an object, by an engine or other similar device. ... A remote camera captures a close_up view of a Space Shuttle Main Engine during a test firing at the John C. Stennis Space Center in Hancock County, Mississippi Spacecraft propulsion is used to change the velocity of spacecraft and artificial satellites, or in short, to provide delta_v. ...


Non-impulsive maneuvers

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. In classical mechanics, the impulse of a constant force is the product of the force and the time during which it acts. ... An ion engine test An ion thruster is a type of spacecraft propulsion that uses beams of ions for propulsion. ...


Finite Burn Trajectories

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. Space has been an interest for philosophers and scientists for much of human history. ... A space rendezvous between two spacecraft, often between a spacecraft and a space station, is an orbital maneuver where the two arrive at the same orbit, make the orbital velocities the same, and bring them together (an approach maneuver, taxiing maneuver); it may or may not include docking. ... The Space Shuttle Discovery as seen from the International Space Station. ... This article or section is in need of attention from an expert on the subject. ... In physics, the center of mass of a system of particles is a specific point at which, for many purposes, the systems mass behaves as if it were concentrated. ... Moment of inertia, also called mass moment of inertia and, sometimes, the angular mass, (SI units kg m², Former British units slug ft2), is the rotational analog of mass. ... Specific impulse (usually abbreviated Isp) is a way to describe the efficiency of rocket and jet engines. ... Centroid of a triangle In geometry, the centroid or barycenter of an object in -dimensional space is the intersection of all hyperplanes that divide into two parts of equal moment about the hyperplane. ...


See also


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