In orbital mechanics and aerospace engineering, a gravitational slingshot, gravity assist maneuver, or swing-by is the use of the relative movement and gravity of a planet or other celestial body 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 (both positively and negatively) and/or re-direct the path of a spacecraft.
The "assist" is provided by the motion of the gravitating body as it pulls on the spacecraft. The technique was first proposed as a mid-course manoeuvre in 1961, and used by interplanetary probes from Mariner 10 onwards, including the two Voyager probes' notable fly-bys of Jupiter and Saturn.
Other articles related to "gravity, gravity assist, assist":
... the Planetary Grand Tour multi-planet mission utilizing the gravity-assist technique to reduce the mission duration from forty years to less than ten years ... and the Cassini (Saturn satellite tour) were made possible by the gravity assist method ... Flandro (also in 1965) studied gravity assist trajectories to Pluto these are the basis for the New Horizons mission launched in January 2006, which will arrive at Pluto in ...
... yr, 11 mo, 24 d) Rosetta flew by Mars as a gravity assist on the way to future encounters ... This was for a gravity assist only no data was collected. 416 ... days (1 yr, 1 mo, 20 d) New Horizons flew by Jupiter as a gravity assist en route to Pluto ...
... The new launch profile included a Venus gravity assist, that added eight months to the planned flight time but offered an increase in payload and better alternatives ... the asteroid belt, where a propulsion maneuver would send the spacecraft back toward Earth for a gravity assist boost ... By using gravity assist, NASA can launch spacecraft aboard rockets that have less thrust than would be needed for a direct flight ...
... A well-established way to get more energy from a gravity assist is to fire a rocket engine at periapsis where a spacecraft is at its maximum velocity ... of closest approach (an aerogravity assist), to achieve a larger deflection and hence more energy gain ...
Famous quotes containing the words assist and/or gravity:
“Capital is a result of labor, and is used by labor to assist it in further production. Labor is the active and initial force, and labor is therefore the employer of capital.”
—Henry George (18391897)
“Grown beyond nature now, soft food for worms,
They lift frail heads in gravity and good faith.”
—Derek Mahon (b. 1941)