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40-503: The giant planet is Neptune -sized, about 20-55 Earth-masses ( M E ). It has a radius 6.2 times that of Earth. The star system is 7200 light years from Earth. The planet orbits a close binary , with a more distant binary orbiting at a distance, forming the quadruple star system. The star system has the Kepler Input Catalogue name KIC 4862625 as well as the designation Kepler-64 . The close binary (Aa+Ab) that

80-643: A 2MASS catalogue entry of 2MASS 19525162+3957183 Kian Jin Jek (Chinese: 易建仁, son of Jek Yeun Thong ), from San Francisco, and Robert Gagliano, from Cottonwood, Arizona, spotted the signature of the planet in the Kepler data, and it was reported through the PlanetHunters.org program run by Dr. Chris Lintott , from Oxford University. Kian Jek first spotted a light dip indicative of a transit in May 2011. JKD reported

120-424: A very low-mass brown dwarf and a massive gas giant ( ~13   M J ) are debated. One school of thought is based on planetary formation; the other, on the physics of the interior of planets. Part of the debate concerns whether brown dwarfs must, by definition, have experienced nuclear fusion at some point in their history. The term gas giant was coined in 1952 by science fiction writer James Blish and

160-594: A benchmark system PH1 is used to improve the algorithm and to demonstrate improvement in the detection of circumbinary planets. Giant planet A giant planet , sometimes referred to as a jovian planet ( Jove being another name for the Roman god Jupiter ), is a diverse type of planet much larger than Earth. Giant planets are usually primarily composed of low- boiling point materials ( volatiles ), rather than rock or other solid matter, but massive solid planets can also exist. There are four such planets in

200-424: A layer of liquid metallic hydrogen , with a probable molten core with a rocky composition. Jupiter and Saturn's outermost portion of the hydrogen atmosphere has many layers of visible clouds that are mostly composed of water and ammonia. The layer of metallic hydrogen makes up the bulk of each planet, and is referred to as "metallic" because the very high pressure turns hydrogen into an electrical conductor. The core

240-410: A radius larger than Neptune , giving it a very low mean density . They are cooler and less massive than the inflated low-density hot-Jupiters . The most extreme examples known are the three planets around Kepler-51 which are all Jupiter -sized but with densities below 0.1 g/cm . Because of the limited techniques currently available to detect exoplanets , many of those found to date have been of

280-482: A second. Robert Gagliano performed a systematic search, and confirmed the second dip, and found a third, in February 2012. Using this, Kian predicted another transit, and found it. The planet was subsequently detected by eclipsing binary timing variation method. At the time of discovery, it was the sixth known circumbinary planet. The planet PH1b and were used as a benchmark system for automated detection algorithms. As

320-483: A size associated, in the Solar System, with giant planets. Because these large planets are inferred to share more in common with Jupiter than with the other giant planets, some have claimed that "jovian planet" is a more accurate term for them. Many of the exoplanets are much closer to their parent stars and hence much hotter than the giant planets in the Solar System, making it possible that some of those planets are

360-472: A type not observed in the Solar System. Considering the relative abundances of the elements in the universe (approximately 98% hydrogen and helium) it would be surprising to find a predominantly rocky planet more massive than Jupiter. On the other hand, models of planetary-system formation have suggested that giant planets would be inhibited from forming as close to their stars as many of the extrasolar giant planets have been observed to orbit. The bands seen in

400-487: Is 318 times as massive as Earth: M J = 3.1782838 × 10 2 M ⊕ . {\displaystyle M_{\mathrm {J} }=3.1782838\times 10^{2}M_{\oplus }.} Jupiter's mass is 2.5 times that of all the other planets in the Solar System combined—this is so massive that its barycenter with the Sun lies beyond the Sun's surface at 1.068  solar radii from

440-555: Is about 1 ⁄ 1000 as massive as the Sun (is about 0.1%  M ☉ ): M J = 1 1047.348644 ± 0.000017 M ⊙ ≈ ( 9.547919 ± 0.000002 ) × 10 − 4 M ⊙ . {\displaystyle M_{\mathrm {J} }={\frac {1}{1047.348644\pm 0.000017}}M_{\odot }\approx (9.547919\pm 0.000002)\times 10^{-4}M_{\odot }.} Jupiter

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480-605: Is also some rock and gas, but various proportions of ice–rock–gas could mimic pure ice, so that the exact proportions are unknown. Uranus and Neptune have very hazy atmospheric layers with small amounts of methane, giving them light aquamarine colors. Both have magnetic fields that are sharply inclined to their axes of rotation. Unlike the other giant planets, Uranus has an extreme tilt that causes its seasons to be severely pronounced. The two planets also have other subtle but important differences. Uranus has more hydrogen and helium than Neptune despite being less massive overall. Neptune

520-625: Is hydrogen, helium, and traces of other gases above their critical points. The observable atmospheres of all these planets (at less than a unit optical depth ) are quite thin compared to their radii, only extending perhaps one percent of the way to the center. Thus, the observable parts are gaseous (in contrast to Mars and Earth, which have gaseous atmospheres through which the crust can be seen). The rather misleading term has caught on because planetary scientists typically use rock , gas , and ice as shorthands for classes of elements and compounds commonly found as planetary constituents, irrespective of

560-862: Is important to note that more recent research has called into question the likelihood of massive solid planet formation around very massive stars( https://arxiv.org/pdf/1103.0556 ). Studies have shown that the ratio of protoplanetary disk mass to stellar mass decreases rapidly for stars above 10 solar masses, falling to less than 10^-4. Furthermore, no protoplanetary disks have been observed around O-type stars to date. The original suggestion of massive solid planets forming around 5-120 solar mass stars, presented in earlier literature, lacks substantial supporting evidence or citations to planetary formation theories. The study in question primarily focused on simulating mass-radius relationships for rocky planets, including hypothetical super-massive solid planets, but did not investigate whether planetary formation theories actually support

600-490: Is the unit of mass equal to the total mass of the planet Jupiter . This value may refer to the mass of the planet alone, or the mass of the entire Jovian system to include the moons of Jupiter . Jupiter is by far the most massive planet in the Solar System . It is approximately 2.5 times as massive as all of the other planets in the Solar System combined. Jupiter mass is a common unit of mass in astronomy that

640-590: Is therefore denser and has much more internal heat and a more active atmosphere. The Nice model , in fact, suggests that Neptune formed closer to the Sun than Uranus did, and should therefore have more heavy elements. Massive solid planets seemingly can also exist, though their formation mechanisms and occurrence remain subjects of ongoing research and debate. The possibility of solid planets up to thousands of Earth masses forming around massive stars ( B-type and O-type stars; 5–120 solar masses) has been suggested in some earlier studies. The hypothesis proposed that

680-500: Is thought to consist of heavier elements at such high temperatures (20,000 K) and pressures that their properties are poorly understood. Ice giants have distinctly different interior compositions from gas giants. The Solar System's ice giants, Uranus and Neptune , have a hydrogen-rich atmosphere that extends from the cloud tops down to about 80% (Uranus) or 85% (Neptune) of their radius. Below this, they are predominantly "icy", i.e. consisting mostly of water, methane, and ammonia. There

720-543: Is used to indicate the masses of other similarly-sized objects, including the outer planets , extrasolar planets , and brown dwarfs , as this unit provides a convenient scale for comparison. The current best known value for the mass of Jupiter can be expressed as 1 898 130   yottagrams : M J = ( 1.89813 ± 0.00019 ) × 10 27  kg , {\displaystyle M_{\mathrm {J} }=(1.89813\pm 0.00019)\times 10^{27}{\text{ kg}},} which

760-626: The International Astronomical Union defined the nominal Jovian mass parameter to remain constant regardless of subsequent improvements in measurement precision of M J . This constant is defined as exactly ( G M ) J N = 1.266 8653 × 10 17  m 3 / s 2 {\displaystyle ({\mathcal {GM}})_{\mathrm {J} }^{\mathrm {N} }=1.266\,8653\times 10^{17}{\text{ m}}^{3}/{\text{s}}^{2}} If

800-683: The Solar System : Jupiter , Saturn , Uranus , and Neptune . Many extrasolar giant planets have been identified. Giant planets are sometimes known as gas giants , but many astronomers now apply the term only to Jupiter and Saturn, classifying Uranus and Neptune, which have different compositions, as ice giants . Both names are potentially misleading; the Solar System's giant planets all consist primarily of fluids above their critical points , where distinct gas and liquid phases do not exist. Jupiter and Saturn are principally made of hydrogen and helium , whilst Uranus and Neptune consist of water, ammonia , and methane . The defining differences between

840-457: The atmosphere of Jupiter are due to counter-circulating streams of material called zones and belts, encircling the planet parallel to its equator. The zones are the lighter bands, and are at higher altitudes in the atmosphere. They have an internal updraft and are high-pressure regions. The belts are the darker bands, are lower in the atmosphere, and have an internal downdraft. They are low-pressure regions. These structures are somewhat analogous to

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880-453: The exoplanets that are easiest to detect. These are called hot Jupiters and hot Neptunes because they have very high surface temperatures. Hot Jupiters were, until the advent of space-borne telescopes, the most common form of exoplanet known, due to the relative ease of detecting them with ground-based instruments. Giant planets are commonly said to lack solid surfaces, but it is more accurate to say that they lack surfaces altogether since

920-478: The protoplanetary disk around such stars would contain enough heavy elements, and that high UV radiation and strong winds could photoevaporate the gas in the disk, leaving just the heavy elements. For comparison, Neptune's mass equals 17 Earth masses, Jupiter has 318 Earth masses, and the 13 Jupiter-mass limit used in the IAU 's working definition of an exoplanet equals approximately 4000 Earth masses. However, it

960-469: The Sun's center. Because the mass of Jupiter is so large compared to the other objects in the Solar System , the effects of its gravity must be included when calculating satellite trajectories and the precise orbits of other bodies in the Solar System, including the Moon and even Pluto. Theoretical models indicate that if Jupiter had much more mass than it does at present, its atmosphere would collapse, and

1000-477: The Sun, the value of the GM product is known to many orders of magnitude more precisely than either factor independently. The limited precision available for G limits the uncertainty of the derived mass. For this reason, astronomers often prefer to refer to the gravitational parameter, rather than the explicit mass. The GM products are used when computing the ratio of Jupiter mass relative to other objects. In 2015,

1040-420: The close binary pair. The distant binary (Ba+Bb) have a pair separation of 60 AU. The two stars are (Ba) 0.99  M ☉ G-type main-sequence star and (Bb) 0.51  M ☉ red dwarf. The quadruple star system has an estimated age of two billion years (2 gigayears). The system is located at right ascension 19 52 51.624 declination +39° 57′ 18.36″, so also has

1080-573: The composition of the planet, especially on the amount of helium and deuterium present. The Extrasolar Planets Encyclopaedia includes objects up to 60 Jupiter masses, and the Exoplanet Data Explorer up to 24 Jupiter masses. A giant planet is a massive planet and has a thick atmosphere of hydrogen and helium . They may have a condensed "core" of heavier elements, delivered during the formation process. This core may be partially or completely dissolved and dispersed throughout

1120-413: The existence of such objects. The authors of that study acknowledged that "Such massive exoplanets are not yet known to exist." Given these considerations, the formation and existence of massive solid planets around very massive stars remain speculative and require further research and observational evidence. A super-puff is a type of exoplanet with a mass only a few times larger than Earth ’s but

1160-447: The explicit mass of Jupiter is needed in SI units, it can be calculated by dividing GM by G , where G is the gravitational constant . The majority of Jupiter's mass is hydrogen and helium. These two elements make up more than 87% of the total mass of Jupiter. The total mass of heavy elements other than hydrogen and helium in the planet is between 11 and 45  M E . The bulk of

1200-565: The gases that form them simply become thinner and thinner with increasing distance from the planets' centers, eventually becoming indistinguishable from the interplanetary medium. Therefore, landing on a giant planet may or may not be possible, depending on the size and composition of its core. Gas giants consist mostly of hydrogen and helium. The Solar System's gas giants, Jupiter and Saturn , have heavier elements making up between 3 and 13 percent of their mass. Gas giants are thought to consist of an outer layer of molecular hydrogen , surrounding

1240-537: The high and low-pressure cells in Earth's atmosphere, but they have a very different structure—latitudinal bands that circle the entire planet, as opposed to small confined cells of pressure. This appears to be a result of the rapid rotation and underlying symmetry of the planet. There are no oceans or landmasses to cause local heating and the rotation speed is much higher than that of Earth. There are smaller structures as well: spots of different sizes and colors. On Jupiter,

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1280-438: The hydrogen/helium envelope. In "traditional" giant planets such as Jupiter and Saturn (the gas giants) hydrogen and helium make up most of the mass of the planet, whereas they only make up an outer envelope on Uranus and Neptune , which are instead mostly composed of water , ammonia , and methane and therefore increasingly referred to as " ice giants ". Extrasolar giant planets that orbit very close to their stars are

1320-419: The mass range between that of large giant planets and the lowest-mass stars . The 13-Jupiter-mass ( M J ) cutoff is a rule of thumb rather than something of precise physical significance. Larger objects will burn most of their deuterium and smaller ones will burn only a little, and the 13   M J value is somewhere in between. The amount of deuterium burnt depends not only on the mass but also on

1360-467: The matter's phase . In the outer Solar System, hydrogen and helium are referred to as gas ; water, methane, and ammonia as ice ; and silicates and metals as rock . When deep planetary interiors are considered, it may not be far off to say that, by ice astronomers mean oxygen and carbon , by rock they mean silicon , and by gas they mean hydrogen and helium. The many ways in which Uranus and Neptune differ from Jupiter and Saturn have led some to use

1400-726: The most noticeable of these features is the Great Red Spot , which has been present for at least 300 years. These structures are huge storms. Some such spots are thunderheads as well. Solar System   → Local Interstellar Cloud   → Local Bubble   → Gould Belt   → Orion Arm   → Milky Way   → Milky Way subgroup   → Local Group → Local Sheet → Virgo Supercluster → Laniakea Supercluster   → Local Hole   → Observable universe   → Universe Each arrow ( → ) may be read as "within" or "part of". Jupiter mass The Jupiter mass , also called Jovian mass ,

1440-414: The planet circles has an orbital period of 20 days. They form an eclipsing binary pair. The two stars are (Aa) 1.384 solar mass ( M ☉ ) F-type main-sequence star and (Ab) 0.336  M ☉ red dwarf . The planet orbits this binary pair in a 138.3-day orbit. The binary pairs have a separation of 1000 AUs . A photometric-dynamical model was used to model the planetary system of

1480-549: The planet would shrink. For small changes in mass, the radius would not change appreciably, but above about 500  M E (1.6 Jupiter masses) the interior would become so much more compressed under the increased pressure that its volume would decrease despite the increasing amount of matter. As a result, Jupiter is thought to have about as large a diameter as a planet of its composition and evolutionary history can achieve. The process of further shrinkage with increasing mass would continue until appreciable stellar ignition

1520-606: The term only for planets similar to the latter two. With this terminology in mind, some astronomers have started referring to Uranus and Neptune as ice giants to indicate the predominance of the ices (in fluid form) in their interior composition. The alternative term jovian planet refers to the Roman god Jupiter —the genitive form of which is Jovis , hence Jovian —and was intended to indicate that all of these planets were similar to Jupiter. Objects large enough to start deuterium fusion (above 13 Jupiter masses for solar composition) are called brown dwarfs , and these occupy

1560-475: Was achieved, as in high-mass brown dwarfs having around 50 Jupiter masses. Jupiter would need to be about 80 times as massive to fuse hydrogen and become a star . The mass of Jupiter is derived from the measured value called the Jovian mass parameter , which is denoted with GM J . The mass of Jupiter is calculated by dividing GM J by the constant G . For celestial bodies such as Jupiter, Earth and

1600-484: Was originally used to refer to all giant planets. Arguably it is something of a misnomer, because throughout most of the volume of these planets the pressure is so high that matter is not in gaseous form. Other than the upper layers of the atmosphere, all matter is likely beyond the critical point , where there is no distinction between liquids and gases. Fluid planet would be a more accurate term. Jupiter also has metallic hydrogen near its center, but much of its volume

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