paragraph_text: 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 to save propellant and reduce expense. Gravity assistance can be used to accelerate a spacecraft, that is, to increase or decrease its speed or redirect its path. The ``assist ''is provided by the motion of the gravitating body as it pulls on the spacecraft. The gravity assist maneuver was first used in 1959 when the Soviet probe Luna 3 photographed the far side of Earth's Moon and it was used by interplanetary probes from Mariner 10 onwards, including the two Voyager probes' notable flybys of Jupiter and Saturn.

paragraph_text: HD 1461 b is an extrasolar planet, orbiting the 6th magnitude G-type star HD 1461, 76.5 light years away in the constellation Cetus. This planet has a minimum mass 6.4 times that of Earth and orbits at a distance of 0.0634 AU with an eccentricity of less than 0.131. It is currently unknown whether the planet is a gas giant like Uranus or Neptune, or has terrestrial composition like CoRoT-7 b. This planet was announced on 13 December 2009 after it was discovered using radial velocity measurements taken at the Keck and Anglo-Australian Observatories.

paragraph_text: HD 11964 c is an extrasolar planet approximately 110 light-years away in the constellation of Cetus. The planet was discovered in a close-orbit around the yellow subgiant star HD 11964. The planet has a minimum mass 35 times the mass of Earth and is located in a mildly eccentric orbit which takes almost 38 days to complete. HD 11964 c was a possible planet discovered on the same day as HD 11964 b in 2005. HD 11964 c was first proposed in a paper published in 2007, and finally confirmed with new data presented in a review of multi-planet systems which appeared on the arXiv preprint website in 2008.

paragraph_text: HAT-P-9b is an exoplanet approximately 1500 light years away in the constellation Auriga. This planet was found by the transit method on June 26, 2008. It has a mass 78% that of Jupiter and a radius 140% that of Jupiter. As with most transiting planets, this planet is a hot Jupiter, meaning this Jupiter-like planet orbits extremely close to its parent star, taking only 3.92 days to orbit.

paragraph_text: Planet of the Apes Created by Pierre Boulle Original work La Planète des singes (1963) Print publications Novel (s) La Planète des singes (1963) Comics List of comics Films and television Film (s) Original series Planet of the Apes (1968) Beneath the Planet of the Apes (1970) Escape from the Planet of the Apes (1971) Conquest of the Planet of the Apes (1972) Battle for the Planet of the Apes (1973) Remake Planet of the Apes (2001) Reboot series Rise of the Planet of the Apes (2011) Dawn of the Planet of the Apes (2014) War for the Planet of the Apes (2017) Television series Planet of the Apes (1974) Return to the Planet of the Apes (1975 -- 1976) Games Video game (s) Planet of the Apes (2001) Revenge of the Apes (2003) Planet of the Apes: Last Frontier (2017)

paragraph_text: HD 30177 b is an extrasolar planet located approximately 181.6 light-years away in the constellation of Dorado, orbiting the star HD 30177. This is one of the most massive planets ever detected by the radial velocity method. In addition, the planet orbits far from the star, about 4 AU away, taking 2770 days (7.58 years) to orbit the star. Even though the massive planet is orbiting at 4 AU from the star, the radial velocity semi-amplitude is high, around 146.8±2.8 m/s. Since the inclination (and thus the true mass) is not known, this planet candidate may in fact be a brown dwarf.

paragraph_text: For a decade from 1963 to about 1973, a substantial number of astronomers accepted a claim by Peter van de Kamp that he had detected, by using astrometry, a perturbation in the proper motion of Barnard's Star consistent with its having one or more planets comparable in mass with Jupiter. Van de Kamp had been observing the star from 1938, attempting, with colleagues at the Sproul Observatory at Swarthmore College, to find minuscule variations of one micrometre in its position on photographic plates consistent with orbital perturbations that would indicate a planetary companion; this involved as many as ten people averaging their results in looking at plates, to avoid systemic individual errors. Van de Kamp's initial suggestion was a planet having about 1.6 MJ at a distance of 4.4 AU in a slightly eccentric orbit, and these measurements were apparently refined in a 1969 paper. Later that year, Van de Kamp suggested that there were two planets of 1.1 and 0.8 MJ.

paragraph_text: The planet Neptune was mathematically predicted before it was directly observed. With a prediction by Urbain Le Verrier, telescopic observations confirming the existence of a major planet were made on the night of September 23 -- 24, 1846, at the Berlin Observatory, by astronomer Johann Gottfried Galle (assisted by Heinrich Louis d'Arrest), working from Le Verrier's calculations. It was a sensational moment of 19th century science and dramatic confirmation of Newtonian gravitational theory. In François Arago's apt phrase, Le Verrier had discovered a planet ``with the point of his pen ''.

paragraph_text: HD 215497 c is an extrasolar planet which orbits the G-type main sequence star HD 215497, located approximately 142 light years away in the constellation Tucana. This planet has at least one-thirds the mass of Jupiter and takes 568 days to orbit the star at a semimajor axis of 1.282 AU. This planet was detected by HARPS on October 19, 2009, together with 29 other planets, including HD 215497 b.

paragraph_text: HD 215497 b is an extrasolar planet which orbits the K-type main sequence star HD 215497, located approximately 142 light years away in the constellation Tucana. This planet has at least 6.6 times the mass of Earth. This planet was detected by HARPS on October 19, 2009, together with 29 other planets, including HD 215497 c.

paragraph_text: Neptune is the eighth and farthest known planet from the Sun in the Solar System. In the Solar System, it is the fourth - largest planet by diameter, the third-most - massive planet, and the densest giant planet. Neptune is 17 times the mass of Earth and is slightly more massive than its near - twin Uranus, which is 15 times the mass of Earth and slightly larger than Neptune. Neptune orbits the Sun once every 164.8 years at an average distance of 30.1 astronomical units (4.50 × 10 km). It is named after the Roman god of the sea and has the astronomical symbol ♆, a stylised version of the god Neptune's trident.

paragraph_text: HD 45350 b is an extrasolar planet located approximately 160 light-years away in the constellation of Auriga. It has a minimum mass about 1.79 times that of Jupiter. The mean distance of the planet from the star is more than the distance between Mars and the Sun, but the eccentricity of the orbit is nothing short of remarkable; at periastron the planet is as close to the star as Mercury is from the Sun, but at apastron it is 8 times further. No doubt seasons on the planet would be extreme.

paragraph_text: HD 8535 b (also known as HIP 6511 b) is an extrasolar planet which orbits the G-type main sequence star HD 8535, located approximately 171 light years away in the constellation Phoenix. This planet has at least five-eighths the mass of Jupiter and takes 3.6 years to orbit the star at a semimajor axis of 2.47 AU. However unlike most other known exoplanets, its eccentricity is not known, but it is typical that its inclination is not known. This planet was detected by HARPS on October 19, 2009, together with 29 other planets.

paragraph_text: HD 11506 b is an extrasolar planet that orbits the star HD 11506 167 light years away in the constellation of Cetus. This planet was discovered in 2007 by the N2K Consortium using the Keck telescope to detect the radial velocity variation of the star caused by the planet. A second planet, HD 11506 c, was discovered in 2015.

paragraph_text: 11 Ursae Minoris b is an extrasolar planet which orbits the K-type giant star 11 Ursae Minoris, located approximately 390 light years away in the constellation Ursa Minor. This planet has mass 10.5 MJ. However, since the mass is at lower limit and since inclination is not known, the actual mass is unknown. This planet may actually be a brown dwarf if a true mass is over 13 times that of Jupiter. This planet takes 17 months to orbit the star at the average distance of 1.54 AU in a circular orbit. This superjovian planet was detected by radial velocity method on August 12, 2009.

paragraph_text: HD 28254 b (also known as HIP 20606 b) is an extrasolar planet which orbits the G-type main sequence star HD 28254, located approximately 178 light years away in the constellation Dorado. This planet has at least seven-sixths the mass of Jupiter and takes over three years to orbit the star at a semimajor axis of 2.01 AU. However unlike most other known exoplanets, its eccentricity is not known, but it is typical that its inclination is not known. This planet was detected by HARPS on October 19, 2009, together with 29 other planets.

paragraph_text: It was only the orbit of the planet Mercury that Newton's Law of Gravitation seemed not to fully explain. Some astrophysicists predicted the existence of another planet (Vulcan) that would explain the discrepancies; however, despite some early indications, no such planet could be found. When Albert Einstein formulated his theory of general relativity (GR) he turned his attention to the problem of Mercury's orbit and found that his theory added a correction, which could account for the discrepancy. This was the first time that Newton's Theory of Gravity had been shown to be less correct than an alternative.

paragraph_text: HD 7199 is a K-class star located in the constellation Tucana. The High Accuracy Radial Velocity Planet Searcher (HARPS) in Chile found it to have a planet either 0.290 the mass of Jupiter or 92 times the mass of Earth with an orbital period of 615 days.

paragraph_text: Neptune is the eighth and farthest known planet from the Sun in the Solar System. In the Solar System, it is the fourth - largest planet by diameter, the third-most - massive planet, and the densest giant planet. Neptune is 17 times the mass of Earth and is slightly more massive than its near - twin Uranus, which is 15 times the mass of Earth and slightly larger than Neptune. Neptune orbits the Sun once every 164.8 years at an average distance of 30.1 AU (4.5 billion km). It is named after the Roman god of the sea and has the astronomical symbol ♆, a stylised version of the god Neptune's trident.

paragraph_text: Since 1973 a number of automated spacecraft have visited Jupiter, most notably the Pioneer 10 space probe, the first spacecraft to get close enough to Jupiter to send back revelations about the properties and phenomena of the Solar System's largest planet. Flights to other planets within the Solar System are accomplished at a cost in energy, which is described by the net change in velocity of the spacecraft, or delta-v. Entering a Hohmann transfer orbit from Earth to Jupiter from low Earth orbit requires a delta-v of 6.3 km/s which is comparable to the 9.7 km/s delta-v needed to reach low Earth orbit. Gravity assists through planetary flybys can be used to reduce the energy required to reach Jupiter, albeit at the cost of a significantly longer flight duration.

Question: What spacecraft used the gravitational pull of the planet to whose mass the other planets were comparable?
Answer: Voyager probes