Wiktionary
alt. (context astrophysics English) The favorable alteration of the speed and trajectory of a spacecraft as a result of its passing near to a celestial body. n. (context astrophysics English) The favorable alteration of the speed and trajectory of a spacecraft as a result of its passing near to a celestial body.
Wikipedia
In orbital mechanics and aerospace engineering, a gravitational slingshot, gravity assist maneuver, or swing-by is the use of the relative movement (e.g. orbit around the Sun) and gravity of a planet or other astronomical object to alter the path and speed of a spacecraft, typically in order to save propellant, time, and expense. Gravity assistance can be used to accelerate a spacecraft, that is, to increase or decrease its speed and/or redirect its path. The "assist" is provided by the motion of the gravitating body as it pulls on the spacecraft. It was used by interplanetary probes from Mariner 10 onwards, including the two Voyager probes' notable flybys of Jupiter and Saturn.
Usage examples of "gravity assist".
Discovery was revisiting Earth for its final gravity assist before Jupiter.
Weightlessness wasn't bad for such things, except that the people involved had to hang on to each other to keep from coming apart: no gravity assist there.
Anyway, when we dive near a sun to get a gravity assist, I don't want solar radiation sleeting through Hecate, so I mounted this mucking great water tank alongside the cabin for a shield.
Anyway, when we dive near a sun to get a gravity assist, I don’.