Query: Jupiter's climate change is due to shifts in internal turbulence fueled from an internal heat source - the planet radiates twice as much energy as it receives from the sun.

Relevant passages:
Jupiter <=SEP=> Jupiter is the fifth planet from the Sun and the largest in the Solar System . It is a giant planet with a mass one-thousandth that of the Sun , but two and a half times that of all the other planets in the Solar System combined . Jupiter and Saturn are gas giants ; the other two giant planets , Uranus and Neptune are ice giants . Jupiter has been known to astronomers since antiquity . The Romans named it after their god Jupiter . When viewed from Earth , Jupiter can reach an apparent magnitude of − 2.94 , bright enough for its reflected light to cast shadows , and making it on average the third-brightest object in the night sky after the Moon and Venus .   Jupiter is primarily composed of hydrogen with a quarter of its mass being helium , though helium comprises only about a tenth of the number of molecules . It may also have a rocky core of heavier elements , but like the other giant planets , Jupiter lacks a well-defined solid surface . Because of its rapid rotation , the planet 's shape is that of an oblate spheroid ( it has a slight but noticeable bulge around the equator ) . The outer atmosphere is visibly segregated into several bands at different latitudes , resulting in turbulence and storms along their interacting boundaries . A prominent result is the Great Red Spot , a giant storm that is known to have existed since at least the 17th century when it was first seen by telescope . Surrounding Jupiter is a faint planetary ring system and a powerful magnetosphere . Jupiter has at least 67 moons , including the four large Galilean moons discovered by Galileo Galilei in 1610 . Ganymede , the largest of these , has a diameter greater than that of the planet Mercury .   Jupiter has been explored on several occasions by robotic spacecraft , most notably during the early Pioneer and Voyager flyby missions and later by the Galileo orbiter . In late February 2007 , Jupiter was visited by the New Horizons probe , which used Jupiter 's gravity to increase its speed and bend its trajectory en route to Pluto . The latest probe to visit the planet is Juno , which entered into orbit around Jupiter on July 4 , 2016 . Future targets for exploration in the Jupiter system include the probable ice-covered liquid ocean of its moon Europa .

Neptune <=SEP=> 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 is denser and physically smaller than Uranus because Neptune 's greater mass gravitationally compresses the atmosphere more . Neptune orbits the Sun once every 164.8 years at an average distance of 30.1 AU . It is named after the Roman god of the sea and has the astronomical symbol ♆ , a stylised version of the god Neptune 's trident .   Neptune is not visible to the unaided eye and is the only planet in the Solar System found by mathematical prediction rather than by empirical observation . Unexpected changes in the orbit of Uranus led Alexis Bouvard to deduce that its orbit was subject to gravitational perturbation by an unknown planet . Neptune was subsequently observed with a telescope on 23 September 1846 by Johann Galle within a degree of the position predicted by Urbain Le Verrier . Its largest moon , Triton , was discovered shortly thereafter , though none of the planet 's remaining known 14 moons were located telescopically until the 20th century . The planet 's distance from Earth gives it a very small apparent size , making it challenging to study with Earth-based telescopes . Neptune was visited by Voyager 2 , when it flew by the planet on 25 August 1989 . The advent of the Hubble Space Telescope and large ground-based telescopes with adaptive optics has recently allowed for additional detailed observations from afar .   Neptune 's composition can be compared and contrasted with the Solar System 's other giant planets . Like Jupiter and Saturn , Neptune 's atmosphere is composed primarily of hydrogen and helium , along with traces of hydrocarbons and possibly nitrogen , but it contains a higher proportion of `` ices '' such as water , ammonia , and methane . However , its interior , like that of Uranus , is primarily composed of ices and rock , which is why Uranus and Neptune are normally considered `` ice giants '' to emphasise this distinction . Traces of methane in the outermost regions in part account for the planet 's blue appearance .   In contrast to the hazy , relatively featureless atmosphere of Uranus , Neptune 's atmosphere has active and visible weather patterns . For example , at the time of the Voyager 2 flyby in 1989 , the planet 's southern hemisphere had a Great Dark Spot comparable to the Great Red Spot on Jupiter . These weather patterns are driven by the strongest sustained winds of any planet in the Solar System , with recorded wind speeds as high as 2100 km/h . Because of its great distance from the Sun , Neptune 's outer atmosphere is one of the coldest places in the Solar System , with temperatures at its cloud tops approaching 55 K. Temperatures at the planet 's centre are approximately 5400 K. Neptune has a faint and fragmented ring system ( labelled `` arcs '' ) , which was first detected during the 1960s and confirmed by Voyager 2 .