In the gravitational two-body problem, the specific orbital energy (or vis-viva energy) of two orbiting bodies is the constant sum of their mutual potential energy () and their total kinetic energy (), divided by the reduced mass.[1] According to the orbital energy conservation equation (also referred to as vis-viva equation), it does not vary with time:
where
is the relative orbital speed;
is the orbital distance between the bodies;
is the sum of the standard gravitational parameters of the bodies;
is the specific relative angular momentum in the sense of relative angular momentum divided by the reduced mass;
is the orbital eccentricity;
is the semi-major axis.
It is typically expressed in (megajoule per kilogram) or (squared kilometer per squared second). For an elliptic orbit the specific orbital energy is the negative of the additional energy required to accelerate a mass of one kilogram to escape velocity (parabolic orbit). For a hyperbolic orbit, it is equal to the excess energy compared to that of a parabolic orbit. In this case the specific orbital energy is also referred to as characteristic energy.
gravitational two-body problem, the specificorbitalenergy ε {\displaystyle \varepsilon } (or vis-viva energy) of two orbiting bodies is the constant sum of...
instantaneous orbital speed at a given point of the orbit can be computed from its distance to the central body and the object's specificorbitalenergy, sometimes...
Specificenergy or massic energy is energy per unit mass. It is also sometimes called gravimetric energy density, which is not to be confused with energy...
standard assumptions, specificorbitalenergy ( ϵ {\displaystyle \epsilon \,} ) of elliptic orbit is negative and the orbitalenergy conservation equation...
the specificorbitalenergy is independent of the eccentricity. Using the virial theorem to find: the time-average of the specific potential energy is...
are minimum-energy escape trajectories, separating positive-energy hyperbolic trajectories from negative-energy elliptic orbits. The orbital velocity (...
astronautics, the Hohmann transfer orbit (/ˈhoʊmən/) is an orbital maneuver used to transfer a spacecraft between two orbits of different altitudes around...
astrodynamics, the orbital eccentricity of an astronomical object is a dimensionless parameter that determines the amount by which its orbit around another...
In spaceflight, an orbital maneuver (otherwise known as a burn) is the use of propulsion systems to change the orbit of a spacecraft. For spacecraft far...
elliptical orbits. The semi major axis is directly linked to the specificorbitalenergy ( ϵ {\displaystyle \epsilon \,} ) or characteristic energy C 3 {\displaystyle...
Orbital decay is a gradual decrease of the distance between two orbiting bodies at their closest approach (the periapsis) over many orbital periods. These...
kg). A related quantity is the specificorbitalenergy which is essentially the sum of the kinetic and potential energy divided by the mass. An object...
burn its fuel is at the lowest possible orbital periapsis, when its orbital velocity (and so, its kinetic energy) is greatest. In some cases, it is even...
semi-major axis and the orbital period of a satellite that can be reduced to a constant of the central body. Specificorbitalenergy, another conserved quantity...
2015-03-07. "FCC Enters Orbital Debris Debate". Space.com. Archived from the original on March 8, 2005. "US Government Orbital Debris Standard Practices"...
mass Specific modulus, a materials property consisting of the elastic modulus per mass density of a material Specificorbitalenergy, orbitalenergy per...
hyperbolic orbits, μ is twice the semi-major axis times the negative of the specificorbitalenergy, where the latter is defined as the total energy of the...
problem of orbital mechanics. Although a Lagrange point is just a point in empty space, its peculiar characteristic is that it can be orbited by a Lissajous...
Aircraft-specificenergy is very similar to specificorbitalenergy except that it is expressed as a positive quantity. A zero value of aircraft-specific energy...
ρ, where T is the orbital period. See also Kepler’s third law. The application of certain orbits or orbital maneuvers to specific useful purposes has...
orbit at an altitude of 20,200 kilometers (12,600 mi) with an orbital period of almost 12 hours. Geosynchronous orbit (GSO) and geostationary orbit (GEO)...
Orbital elements are the parameters required to uniquely identify a specificorbit. In celestial mechanics these elements are considered in two-body systems...
only a few orbital trajectories possible for indefinite frozen orbits. These would be useful for long-term stays in LLO. Most lunar low orbits below 100...
The orbital period (also revolution period) is the amount of time a given astronomical object takes to complete one orbit around another object. In astronomy...