Editing Hyperbolic trajectory (section)

{{Short description|Concept in astrodynamics}}
[[File:OrbitalEccentricityDemo.svg|thumb|right|The blue path in this image is an example of a hyperbolic trajectory.]]
[[File:Gravity Wells Potential Plus Kinetic Energy - Circle-Ellipse-Parabola-Hyperbola.png|thumb|250px|A hyperbolic trajectory is depicted in the bottom-right quadrant of this diagram, where the [[gravity well|gravitational potential well]] of the central mass shows potential energy, and the kinetic energy of the hyperbolic trajectory is shown in red. The height of the kinetic energy decreases as the speed decreases and distance increases according to Kepler's laws. The part of the kinetic energy that remains above zero total energy is that associated with the hyperbolic excess velocity.]]
{{Astrodynamics}}
In [[astrodynamics]] or [[celestial mechanics]], a '''hyperbolic trajectory''' or '''hyperbolic orbit''' is the trajectory of any object around a [[central body]] with more than enough speed to escape the central object's gravitational pull. The name derives from the fact that according to [[Newton's law of universal gravitation|Newtonian theory]] such an orbit has the shape of a [[hyperbola]]. In more technical terms this can be expressed by the condition that the [[orbital eccentricity]] is greater than one.

Under simplistic assumptions a body traveling along this trajectory will coast towards infinity, settling to a final excess velocity relative to the central body. Similarly to [[parabolic trajectory|parabolic trajectories]], all hyperbolic trajectories are also [[escape trajectory|escape trajectories]]. The [[specific orbital energy|specific energy]] of a hyperbolic trajectory orbit is positive.

Planetary flybys, used for [[Gravity assist|gravitational slingshots]], can be described within the planet's [[Sphere of influence (astrodynamics)|sphere of influence]] using hyperbolic trajectories.