Fomalhaut b’s orbit was also odd and very eccentric. As of May 25, 2013 it is 110 AU from its parent star. [4], A second paper made public a day later and led by Raphael Galicher and Christian Marois at the Herzberg Institute of Astrophysics also independently recovered Fomalhaut b and confirmed the new 0.4 µm detection, claiming the spectral energy distribution (SED) of Fomalhaut b cannot be explained as due to direct or scattered radiation from a massive planet. They considered two models to explain the SED: (1) a large circumplanetary disk around a massive, but unseen, planet and (2) the aftermath of a collision during the past 100 years of two Kuiper belt objects of radii about 50 km.[16]. Left: upper limits on the CO mass present in the Fomalhaut ring, as a function of the collisional partner-to-dust mass ratio f cp (x-axis, where the main colliders are H 2 O and e −), of the CO/H 2 O ice abundance ratio in planetesimals (different line styles) and of the gas kinetic temperature T k (different colours). Fomalhaut B is a flare star of the type known as a BY Draconis variable. The model is simple, adaptable to other debris disks, and can be extended to accommodate multiple planets. [43], On November 13, 2008, astronomers announced an object, which they assumed to be an extrasolar planet, orbiting just inside the outer debris ring. The host star Fomalhaut has apparent magnitude of 1.2, with absolute magnitude of 1.7. paper hinted that it was moving too fast (i.e. Los Angeles, CA – Fomalhaut is a young A-type star approximately twice the mass of our sun, located 25 light years from Earth in the constellation Piscis Austrinus. [45] The mass of the planet, Fomalhaut b, was estimated to be less than three times the mass of Jupiter, and at least the mass of Neptune. Fomalhaut b was initially identified as one of the first exoplanets to be directly imaged: its detection was attributed to reflected light from circumplanetary material (e.g. The star's traditional name derives from Fom al-Haut from scientific Arabic فم الحوت fam al-ḥūt (al-janūbī) "the mouth of the [Southern] Fish" (literally, "mouth of the whale"), a translation of how Ptolemy labeled it. Its mass is 2.6 Jupiters, it takes 1522 years to complete one orbit of its star, and is 160 AU from its star. I nearly had a heart attack at the end of May when I confirmed that Fomalhaut b orbits its parent star. [9] Finally, in 2008, a spectroscopic measurement gave a significantly lower value of 46%. Here, we present optical observations of an exoplanet candidate, Fomalhaut b. Fomalhaut b lies about 119 astronomical units (AU) from the star and 18 AU of the dust belt, matching predictions of its location. Cloud State University Planetarium to the IAU for consideration. The Fomalhaut system had been a target of exoplanet searches since 1993 in part because of its age — it’s relatively young at just 440 million years old — but especially because it radiates more infrared light than expected from the star alone. Alternatively, it could be a conglomeration of rubble from a recent collision between comet-to-asteroid-sized bodies, and not actually a planet.[16][8]. Fomalhaut B is classified as a BY Draconis variable, a star exhibiting variations in luminosity due to the effects of rotation and starspots. Though Fomalhaut is in the main sequence and only a bit larger than the Sun, the star produces considerably more energy in the visible light spectrum, shining with a luminosity around 16 times that … Fomalhaut is a blue dwarf (A3V) star situated 25.13 light years from Earth that is 1.842 times bigger than the Sun, with 1.92 times its mass, and 16.63 times its luminosity. The inner disk is a high-carbon small-grain (10–300 nm) ash disk, clustering at 0.1 AU from the star. [16], Fomalhaut b is orbiting its host star at a wide separation, where forming massive planets is difficult. 2M1207 b, GQ Lup b, DH Tau b, AB Pic b, CHXR 73 b, UScoCTIO 108 b, CT Cha b, 1RXS 1609 b) in that their emission was thought to originate at least in part from a planetary atmosphere. The designation TW Piscis Austrini is astronomical nomenclature for a variable star. Fom b is detected inHST’s F814W (0.7–0.9μm) and F606W (0.45–0.7μm) passbands in 2006. This is an association of stars which share a common motion through space, and have been claimed to be physically associated. [56], LP 876-10 is also associated with the Fomalhaut system, making it a trinary star. Most flare stars are red M-type dwarfs. [35][36] A 2012 study gave a slightly higher age of 440±40 million years. Fomalhaut b’s closest approach to the star (periastron) is approximately 30 au and the orbital period is roughly 1,700 years. The classical astronomer Ptolemy put it in Aquarius, as well as Piscis Austrinus. [31] Dagon was a Semitic deity, often represented as half-man, half-fish. Because such dust is expected to be blown out of the system by stellar radiation pressure on short timescales, its presence indicates a constant replenishment by collisions of planetesimals. In the discovery paper,[1] Kalas and collaborators suggested that Fomalhaut b's emission originates from two sources: from circumplanetary dust scattering starlight and from planet thermal emission. [53], If there are additional planets from 4 to 10 AU, they must be under 20 MJ; if from 2.5 outward, then 30 MJ. Abstract. Fomalhaut, a bright star 7.7 parsecs (25 light-years) from Earth, harbors a belt of cold dust with a structure consistent with gravitational sculpting by an orbiting planet. [7][37] In 2004, a stellar evolutionary model of Fomalhaut yielded a metallicity of 79%. In 2019 a team of researchers analyzing the astrometry, radial velocity measurements, and images of Fomalhaut B suggested the existence of a planet orbiting the star with a mass of 1.2+0.7−0.6 Jupiter Masses, and an poorly defined orbital period of up to 80 years. If Fom b is the dominant perturber of the belt, then to produce the observed disk morphology it must have a mass Mpl < 3MJ, an orbital semimajor axis apl> 101.5 AU, and an orbital eccentricity epl = 0.11–0.13. In the present paper, we reanalyze the multi-epoch ACS/STIS/WFC3 HubbleSpaceTelescope (HST) optical/near-infrared images on which the discovery and some other claims were based. [4] Although the initial discovery paper for Fomalhaut b suggested that its optical brightness may be variable due to planetary accretion, later reanalyses of these data fail to find convincing evidence that Fomalhaut b is indeed variable,[4][16][2] thus eliminating evidence for planetary accretion. instead suggest that Fomalhaut b's light is scattered starlight, not planet thermal emission. [9][10] The process involved public nomination and voting for the new name. They modeled the optical detections and infrared upper limits for Fomalhaut b, showing that Fomalhaut b's emission can be completely explained by starlight scattered by small dust and arguing that this dust surrounds an unseen planetary-mass object. This was the first extrasolar orbiting object to be seen with visible light, captured by the Hubble Space Telescope. However, subsequent studies from the Spitzer Space Telescope[18] and a reanalysis of the original HST data[16][4] 2012, the Spitzer IR non-detection of Fomalhaut b, Astrobites summary of Boley et al. The NASA/ESA Hubble Space Telescope has taken the first visible light snapshot of a planet circling another star. Fomalhaut was the first stellar system with an extrasolar planet candidate (designated Fomalhaut b, later named Dagon) imaged at visible wavelengths. [30] Alternatively, if it is a transient dust cloud it must be extremely young,[4] perhaps having formed within the last few centuries. Next is a disk of larger particles, with inner edge 0.4-1 AU of the star. Observations in 2005 with Keck in theHband (1.5–1.8μm) and in 2008 with Gemini in L-prime (3.2–4μm) gave only upper limits. In 1980, astronomer Jack Robinson proposed that the rising azimuth of Fomalhaut was marked by cairn placements at both the Bighorn and Moose Mountain Medicine Wheels in Wyoming, USA and Saskatchewan, Canada, respectively. [39][40] The dust is distributed in a belt about 25 AU wide. The WGSN's first bulletin of July 2016[27] included a table of the first two batches of names approved by the WGSN, which included the name Fomalhaut for this star. [29] The orbital separation of Fomalhaut b is larger than that for directly imaged planets around β Pictoris and HR 8799 (8–70 AU). [2] However, analysis of Fomalhaut b's astrometry showed that the object has a high eccentricity (e = 0.8), its orbit (projected on the sky) crosses the plane of Fomalhaut's debris ring, and thus it is unlikely to be the object sculpting the debris ring's sharp inner edge. [14] Since 1943, the spectrum of this star has served as one of the stable anchor points by which other stars are classified. Fomalhaut b appears to be moving at about 4 kilometers per second. [1] The shape of its spectrum, as determined from measurements obtained at 0.4 to 0.8 μm, appears similar to that of its host star, suggesting that the emission identifying Fomalhaut b is completely due to scattered starlight. [12] The name Dagon was proposed by Dr. Todd Vaccaro and forwarded by the St. However, Fomalhaut b should be detectable in space-based infrared data if its mass is between 1-3 Jupiter masses. [16] Fomalhaut, K-type main-sequence star TW Piscis Austrini, and M-type, red dwarf star LP 876-10 constitute a triple system, even though the companions are separated by approximately 8 degrees.[17][18]. Following Ptolemy, John Flamsteed in 1725 additionally denoted it 79 Aquarii. Wolk2 1Astrophysics Research Centre, Queen’s University Belfast, University Road, BT7 1NN Belfast, United Kingdom 2Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, 02138 MA, USA 3Center for Cosmology and Astro … On one hand, Fomalhaut b could be a planet less than twice Jupiter's mass that is either enshrouded in a spherical cloud of dust from ongoing planetesimal collisions[4][15] or surrounded by a large circumplanetary ring system,[1] either of which are responsible for scattering the primary star's light and thus making Fomalhaut b visible. [44] A planet's existence had been previously suspected from the sharp, elliptical inner edge of that disk. Its discovery was announced in 2008. The existence of a massive planet orbiting Fomalhaut was first inferred from Hubble observations published in 2005 that resolved the structure of Fomalhaut's massive, cold debris disk (or dust belt/ring). In addi-tion to this published planetary mass companion candidate (called Fomalhaut b), Fomalhaut … This distance is about 18 AU (2.7×109 km; 1.7×109 mi) closer to the star than the inner edge of the debris disk. The collision rate is estimated to be approximately 2000 kilometre-sized comets per day. It is a class A star on the main sequence approximately 25 light-years (7.7 pc) from the Sun as measured by the Hipparcos astrometry satellite. [4] They reanalyzed the original Hubble data using new, more powerful algorithms for separating planet light from starlight and confirmed that Fomalhaut b does exist. [49] In 2012, two independent studies confirmed that Fomalhaut b does exist, but it is shrouded by debris, so it may be a gravitationally-bound accumulation of rubble rather than a whole planet. [15] If Fomalhaut b is instead one of two shepherding planets that together confine the debris disk into a narrow ring,[24] it could be anywhere between several times the mass of Mars to slightly more massive than Earth. It is around 440 million years old, or less than halfway through its one billion year lifespan, and has a surface temperature of around 8,500 kelvins compared to 5,778 K for the Sun . It also bears the Flamsteed designation of 24 Piscis Austrini. The true nature of Fomalhaut b is the subject of significant debate. [18] Furthermore, although the planet was thought to be a plausible explanation for Fomalhaut's eccentric debris ring, measurements in the Kalas et al. Models of Fomalhaut b sculpting Fomalhaut's debris disk identify 0.5 times Jupiter's mass as a plausible … Multiple-star systems hosting multiple debris disks are exceedingly rare. It has a periastron of 7.4 billion km (~50 AU) and an apastron of about 44 billion km (~300 AU). The fluffy morphology of the grains suggests a cometary origin. A circumplanetary ring system is large enough to scatter enough starlight to make Fomalhaut b visible only if it has a radius between 20 and 40 times that of Jupiter's radius. LP 876-10 is a red dwarf of spectral type M4V, and located even further from Fomalhaut A than TW PsA—about 5.7° away from Fomalhaut A in the sky, in the neighbouring constellation Aquarius, whereas both Fomalhaut A and TW PsA are located in constellation Piscis Austrinus. [34], Fomalhaut is a young star, for many years thought to be only 100 to 300 million years old, with a potential lifespan of a billion years. [17] LP 876-10 was originally catalogued as a high-proper-motion star by Willem Luyten in his 1979 NLTT catalogue; however, a precise trigonometric parallax and radial velocity was only measured quite recently. [26][27], On October 24, 2012, a team led by Thayne Currie at the University of Toronto announced the first independent recovery of Fomalhaut b and revived the claim that Fomalhaut b identifies a planet. The object was initially announced in 2008 and confirmed as real in 2012 from images taken with the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope and, according to calculations reported in January 2013,[5][6] has a 1,700-year,[2] highly elliptical orbit. Even though the elliptical path of Fomalhaut b appears to cross through the belt in the future, its orbital plane is likely 17 degrees different from the dust belt’s plane. Fomalhaut's dusty disk is believed to be protoplanetary,[42] and emits considerable infrared radiation. [29] In December 2015, the IAU announced the winning name was Dagon for this planet. Fomalhaut’s mass and radius are, respectively, a little more than twice and a little less than twice solar values. [20] A massive planet on a wide orbit but located interior to this debris ring could clear out parent bodies and dust in its vicinity, leaving the ring appearing to have a sharp inner edge and making it appear offset from the star. a dust ring) and thermal emission from a jovian planet atmosphere. It varies slightly in apparent magnitude, ranging from 6.44 to 6.49 over a 10.3 day period. It was also a marker for the worship of Demeter in Eleusis. However, its southerly declination is not as great as that of stars such as Acrux, Alpha Centauri and Canopus, meaning that, unlike them, Fomalhaut is visible from a large part of the Northern Hemisphere as well. The moving group has an estimated age of 200±100 million years and originated from the same location. [4] Fomalhaut b appears as an unresolved point source in the highest-quality data (at 0.6 μm) which would suggest that its projected emitting area cannot be larger than about 0.25 AU, about 1/4th of the Earth–Sun distance. Fomalhaut's mass is about 1.92 times that of the Sun, its luminosity is about 16.6 times greater, and its diameter is roughly 1.84 times as large. 344–47), "Bulletin of the IAU Working Group on Star Names, No. Although originally thought to be a massive exoplanet, the faintness of Fomalhaut b in the infrared and its failure to perturb Fomalhaut’s debris ring indicate a low mass. [41] The disk is sometimes referred to as "Fomalhaut's Kuiper belt". not apsidally aligned) for this explanation to work. The team attempted to detect Fomalhaut b in the infrared using the Subaru Telescope in Hawaii, but was unable to do so. At a declination of −29.6°, Fomalhaut is located south of the celestial equator, and hence is best viewed from the Southern Hemisphere. [24][25] These results invoked skepticism about Fomalhaut b's status as an extrasolar planet. The F606W flux is variable; the flux in 2006 was about half of that in 2004. Fomalhaut b then began dimming, and by 2014 the telescope could no longer detect it. counterparts. Fomalhaut has been a candidate for planet hunting ever since an excess of dust was discovered around the star in the early 1980s by NASA's Infrared Astronomy Satellite, IRAS. While Fomalhaut is massive, with a mass of 1.9 times that of the Sun, its companion stars are smaller. The revival of the claim that Fomalhaut b is (possibly) a planet after it had been discounted led some to nickname the object a "zombie planet",[28] although this is a non-technical term used in press material and does not appear in any peer-reviewed manuscript. [16], The outermost disk is at a radial distance of 133 AU (1.99×1010 km; 1.24×1010 mi), in a toroidal shape with a very sharp inner edge, all inclined 24 degrees from edge-on. [7][8], The object was one of those selected by the International Astronomical Union as part of their public process for giving proper names to exoplanets. We confirm that [33], Fomalhaut b's position in 2004 and 2006 (ACS), Artistic rendition of Fomalhaut b as a planet which revolves around its parent star, Visualisation of Fomalhaut and Fomalhaut b (artist's impression), Coordinates: 22h 57m 39.1s, −29° 37′ 20″, For the second star in the Fomalhaut system, see, Recovery, independent confirmation by Hubble and further additional findings, List of star systems within 25–30 light-years, "NASA's Hubble Reveals Rogue Planetary Orbit For Fomalhaut B", "Hubble Reveals Rogue Planetary Orbit for Fomalhaut b (News Release Number: STScI-2013-01)", "The Case of the Disappearing Exoplanet - Fomalhaut b was one of the first planets around another star to be directly imaged by telescopes. 2012, the ALMA observations of the Fomalhaut ring system, Researchers find that bright nearby double star Fomalhaut is actually a triple, https://en.wikipedia.org/w/index.php?title=Fomalhaut&oldid=988647788, Articles with Chinese-language sources (zh), Articles with obsolete information from May 2013, All Wikipedia articles in need of updating, Creative Commons Attribution-ShareAlike License, To the Moporr Aboriginal people of South Australia, it is a masculine being called, This page was last edited on 14 November 2020, at 12:32. Fomalhaut by Kalas et al. For the extrasolar planet, see. [9] The metallicity is typically determined by measuring the abundance of iron in the photosphere relative to the abundance of hydrogen. The orbital separation of Fomalhaut b is larger than that for directly imaged planets around β Pictoris and HR 8799(8–70 AU). [7] The surface temperature of the star is around 8,590 K (8,320 °C). Several ground-based observations have searched for this hypothetical Fomalhaut "c" but have yet to find it. [7], Fomalhaut is slightly metal-deficient compared to the Sun, which means it is composed of a smaller percentage of elements other than hydrogen and helium. [11] In December 2015, the IAU announced the winning name was Dagon. [8], In order for Fomalhaut b to be detectable at optical wavelengths, it must have an emitting area much larger than the physical size of a planet,[1] a fact further strengthening the case that what we see as Fomalhaut b is not light coming from a planetary atmosphere. Fomalhaut b has subsequently been described as a low-mass planet whose surrounding dust cloud is entirely responsible for its detection or, most recently, debris from a collision of asteroids instead. [23] On its discovery, the planet was designated Fomalhaut b. Atacama Large Millimeter/submillimeter Array, List of star systems within 25–30 light-years, "VLTI near-IR interferometric observations of Vega-like stars. [1] A spherical cloud of dust with a radius of 0.004 AU (600,000 km; 370,000 mi) can make Fomalhaut b visible. The current designation reflects modern consensus on Bayer's decision, that the star belongs in Piscis Austrinus. We use all available data to reveal that it has faded in brightness and grown in extent, with … A 1997 spectroscopic study measured a value equal to 93% of the Sun's abundance of iron. Subsequent Hubble data obtained in 2010 and 2012 with the STIS instrument by Paul Kalas and collaborators again recovered Fomalhaut b. Nevertheless, back in 2008, astronomers were convinced it was a giant exoplanet about three times the mass of Jupiter; it appeared as a visible moving dot in images snapped by NASA’s Hubble scope. However, longer-term monitoring of Fomalhaut b may show evidence that the object is fading with time. Other members of this group include Castor and Vega. [1][22], Kalas remarked, "It's a profound and overwhelming experience to lay eyes on a planet never before seen. But that’s not all. The non-detections with Subaru and Spitzer imply that Fomalhaut b must have less than twice the mass of Jupiter. Models of Fomalhaut b sculpting the star's debris disk give a mass 0.5 times that of Jupiter. Fomalhaut is a blue dwarf (A3V) star situated 25.13 light years from Earth that is 1.842 times bigger than the Sun, with 1.92 times its mass, and 16.63 times its luminosity. While it is unclear whether Fomal… Fomalhaut b, formally named Dagon (/ˈdeɪɡən/),[3] is a confirmed,[4] directly imaged[1] extrasolar object and candidate planet orbiting the A-type main-sequence star Fomalhaut, approximately 25 light-years away in the constellation of Piscis Austrinus. LP 876-10 is located well within the tidal radius of the Fomalhaut system, which is 1.9 parsecs (6.2 light-years). Analyses of additional STIS data obtained in 2013 and 2014 argue that Fomalhaut b is fading and expanding in size, a behavior that may support the interpretation of Fomalhaut b as a collision between two asteroid-sized objects.[8]. [58], Fomalhaut has had various names ascribed to it through time, and has been recognized by many cultures of the northern hemisphere, including the Arabs, Persians, and Chinese. This visible-light image from the Hubble shows the newly discovered planet, Fomalhaut b, orbiting its parent star. [21] Fomalhaut is the third-brightest star (as viewed from Earth) known to have a planetary system, after the Sun and Pollux. In the 1600s Johann Bayer firmly planted it in the primary position of Piscis Austrinus. [31] At slightly wider scales comparable to the locations of planets around HR 8799, any additional planets must have masses below about 2 to 7 Jupiter masses. [17] Although LP 876-10 is itself catalogued as a binary star in the Washington Double Star Catalog (called "WSI 138"), there was no sign of a close-in stellar companion in the imaging, spectral, or astrometric data in the Mamajek et al. The IR non detections limit Fomalhaut b’s mass to be less than about twice Jupiter’s mass. reported the discovery of a cold dusty debris disk associated with Fomalhaut C, using infrared images from the Herschel Space Observatory. Finally, researchers analyzing September–October 2011 Atacama Large Millimeter Array (ALMA) data for Fomalhaut's debris ring suggested an alternate hypothesis: that the ring could be shaped by much smaller, shepherding planets, neither of which needed to be Fomalhaut b. 1", NameExoWorlds: An IAU Worldwide Contest to Name Exoplanets and their Host Stars, Final Results of NameExoWorlds Public Vote Released, http://www.sctimes.com/story/news/local/2015/12/25/scsu-planetarium-names-exoplanet/77875858/, "ALMA Reveals Workings of Nearby Planetary System", "Shallow Sky Object of the Month: Fomalhaut", "Elusive Planet Reshapes a Ring Around Neighboring Star", "Hubble Directly Observes a Planet Orbiting Another Star", "Hubble snaps first optical photo of exoplanet", Monthly Notices of the Royal Astronomical Society, "The Possible Astrometric Signature of a Planetary-mass Companion to the Nearby Young Star TW Piscis Austrini (Fomalhaut B): Constraints from Astrometry, Radial Velocities, and Direct Imaging", AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 7 日, Astrobites summary of Janson et al. [14], The nature of Fomalhaut b is unclear. Assuming that Fomalhaut b's orbit is in the same plane as the debris disk located exterior to it, it orbits Fomalhaut at a distance of approximately 115 AU (1.72×10 km; 1.07×10 mi). [1][4] However, it may be resolved at slightly longer wavelengths and in the most recently analyzed HST data, which would indicate that its emitting area is larger.[16][8]. In October 2013, Eric Mamajek and collaborators from the RECONS consortium announced that the previously known high-proper-motion star LP 876-10 had a distance, velocity, and color-magnitude position consistent with being another member of the Fomalhaut system. 0.6 and 0.8 μm). [32], At a declination of −29.6°, Fomalhaut is located south of the celestial equator, and hence is best viewed from the Southern Hemisphere. K. Auchettl,3 4 S.J. The mass of Fomalhaut b, if a planet, is highly uncertain. Fomalhaut B has an estimated mass of 0.725 solar masses and a radius 63% that of the Sun. Fomalhaut b and three companions around HR 8799, whose discovery was announced simultaneously, were described as the first directly imaged extrasolar planets[17] (among earlier claims such as e.g. Measurements of Fomalhaut's rotation indicate that the disk is located in the star's equatorial plane, as expected from theories of star and planet formation. Fomalhaut /ˈfoʊməl.hɔːt/,[13] designation Alpha Piscis Austrini (α Piscis Austrini, abbreviated Alpha PsA, α PsA) is the brightest star in the constellation of Piscis Austrinus, the "Southern Fish", and one of the brightest stars in the sky. While smaller than the Sun, it is relatively large for a flare star. Thus, they consider Fomalhaut b to plausibly be a "planet identified from direct imaging" even if Fomalhaut b is not, strictly speaking, a directly imaged planet insofar as the light does not come from a planetary atmosphere. But sensitive infrared Spitzer Space Telescope observations failed to detect Fomalhaut b, implying that Fomalhaut b has less than 1 Jupiter mass. [13] Dagon was a Semitic deity, often represented as half-man, half-fish. Fomalhaut b is a gas giant exoplanet that orbits an A-type star. Its declination is greater than that of Sirius and similar to that of Antares. [24][25] In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN)[26] to catalog and standardize proper names for stars. [47], However, M-band images taken from the MMT Observatory put strong limits on the existence of gas giants within 40 AU of the star,[48] and Spitzer Space Telescope imaging suggested that the object Fomalhaut b was more likely to be a dust cloud. [17] In December 2013, Kennedy et al. discovery in Science. α Piscis Austrini (Latinised to Alpha Piscis Austrini) is the system's Bayer designation. & CLAMPIN M. Fomalhaut is also the setting for numerous works of fiction and games. study. [46] There are indications that the orbit is not apsidally aligned with the dust disk, which may indicate that additional planets may be responsible for the dust disk's structure. [32] Fomalhaut b could have formed in situ if it coalesced from small pebble-sized objects that rapidly formed into a protoplanetary core which in turn accreted a gaseous envelope. Models for Fomalhaut b assuming it is surrounded by a swarm of planetesimals imply that it could be much lower mass (10–100 times the mass of Earth). [17] Hence, "membership" to this dynamical group has no bearing on the age of the Fomalhaut system.[17]. It is 1.9 times more massive and 1.8 times bigger compared with our Sun. NASA released the composite discovery photograph on November 13, 2008, coinciding with the publication of Kalas et al. Fomalhaut b ass eng Stëbswollek, déi 25 Liichtjoer vun eis ewech läit. To explain its current location, Fomalhaut b could have been dynamically scattered by a more massive, unseen body located at smaller separations. Its declination is greater than that of Sirius and similar to that of Antares. A recent age estimate for TW PsA (400±70 million years) agrees very well with the isochronal age for Fomalhaut (450±40 million years), further arguing for the two stars forming a physical binary.[7]. At a system age of ~ 200 Myr, detritus from the formation of the Fomalhaut planetary system still remains. At 40°N, Fomalhaut rises above the horizon for eight hours and reaches only 20° above the horizon, while "[22] In the image, the bright outer oval band is the dust ring, while the features inside of this band represent noise from scattered starlight.[23]. [50][51], Herschel Space Observatory images of Fomalhaut reveal that a large amount of fluffy micrometer-sized dust is present in the outer dust belt. Infrared non-detections suggest that Fomalhaut b cannot be more massive than 2 times Jupiter's mass but a lower limit on the mass depends on uncertain details for the nature of Fomalhaut b, its circumplanetary environment, and the existence of other planet-mass bodies in the system. If Fomalhaut b is a gas giant like Jupiter or Saturn, it probably formed several million years after the host star itself was formed, making it roughly 450 million years old. Here, the former explains most of the 0.6 μm brightness and planet thermal emission contributes to much of the 0.8 μm brightness. It marked the solstice in 2500 BC. Fomalhaut b appears to be moving at about 4 kilometers per second. Fomalhaut — often pronounced FO-MA-LO — is one of those bright stars that appears vivid in our skies due to its close proximity to our home planet. [54], Fomalhaut forms a binary star with the K4-type star TW Piscis Austrini (TW PsA), which lies 0.28 parsecs (0.91 light-years) away from Fomalhaut, and its space velocity agrees with that of Fomalhaut within 0.1±0.5 km/s, consistent with being a bound companion. [28] The process involved public nomination and voting for the new names. The image was published in Science in November 2008. [2], At the optical wavelengths at which Fomalhaut b is detected, it is only about 2.7×10−10 times as bright as the star and is the faintest (intrinsically) extrasolar object yet imaged. At a mere 25 light-years away, Fomalhaut is among the Sun’s closest stellar neighbors. Please update this article to reflect recent events or newly available information. Fomalhaut's Debris Disk and Planet: Constraining the Mass of Fomalhaut b From Disk Morphology 2009 CHIANG E., KITE E., KALAS P., GRAHAM J. Their non-detections with ground-based infrared data suggested that Fomalhaut b had to be less massive than about 3 Jupiter masses. Fomalhaut b's high eccentricity may be evidence for a significant dynamical interaction with a hitherto unseen planet at a smaller orbital separation. Deciphering Fomalhaut b. [59], Fomalhaut/Earthwork B, in Mounds State Park near Anderson, Indiana, lines up with the rising of the star Fomalhaut in the fall months, according to the Indiana Department of Natural Resources. [21], In May 2008, Paul Kalas, James Graham and their collaborators identified Fomalhaut b from Hubble/ACS images taken in 2004 and 2006 at visible wavelengths (i.e. Fomalhaut is surrounded by several debris disks. Assuming that Fomalhaut b's orbit is in the same plane as the debris disk located exterior to it, it orbits Fomalhaut at a distance of approximately 115 AU (1.72×1010 km; 1.07×1010 mi). Fomalhaut can be located in northern latitudes by the fact that the western (right-hand) side of the Square of Pegasus points to it. (2008) was widely regarded as a great success for the direct imaging detection method. Cloud State University Planetarium of St. Cloud, Minnesota, United States of America, to the IAU for consideration. The separation between Fomalhaut A and b is some 100 au or 13 arcsec. [15] It is classified as a Vega-like star that emits excess infrared radiation, indicating it is surrounded by a circumstellar disk. Coordinates: 22h 57m 39.1s, −29° 37′ 20″, This article is about the star. Its current separation from Fomalhaut A is about 0.77 parsecs (2.5 light-years), and it is currently located 0.987 parsecs (3.22 light-years) away from TW PsA (Fomalhaut B). The second star, Fomalhaut B, is 0.7 solar masses, and the third, Fomalhaut C, is tiny red dwarf of only 0.2 solar masses. The innermost disk is unexplained as yet. [52], Observations of the star's outer dust ring by the Atacama Large Millimeter Array point to the existence of two planets in the system, neither one at the orbital radius proposed for the HST-discovered Fomalhaut b. [4] While it is unclear whether Fomalhaut b's orbit will make it cross the debris disk or cross the debris disk only in projection (i.e. [30] The winning name was proposed by Todd Vaccaro and forwarded by the St. If Fomalhaut b is a planet sculpting the debris ring, it probably must be at least Neptune’s mass with the most current models favoring about half Jupiter’s mass. Its discovery was publicly announced on 2008. [63], The New Scientist magazine termed it the "Great Eye of Sauron", due to its shape and debris ring, when viewed from a distance, bearing similarity to the aforementioned "Eye" in the Peter Jackson Lord of the Rings films.[64]. [19] The belt is not centered on the star, and has a sharper inner boundary than would normally be expected. Fomalhaut b is an exoplanet orbiting the star Fomalhaut, located about 25.1 light-years (7.7 pc) away from Solar System. Another contentious issue has been the object's orbit. Estimated to be no more than three times Jupiter's mass, the planet, called Fomalhaut b, orbits the bright southern star Fomalhaut, located 25 light-years away in the constellation Piscis Austrinus (the Southern Fish). At very small, Solar-System-like scales any additional companions must have a mass less than thirteen times the mass of Jupiter. USS Fomalhaut (AK-22) was a United States navy amphibious cargo ship. it is not orbiting in the same plane as the disk), its orbit is not completely nested within the debris disk. They also provided a new detection of Fomalhaut b at 0.4 µm. The geometric center of the disk is offset by about 15 AU (2.2×109 km; 1.4×109 mi) from Fomalhaut. “The NASA/ESA Hubble Space Telescope has taken the first visible light snapshot of a planet circling another star. If Fom b is the dominant perturber of the belt, then to produce the observed disk … Radius and age of α PsA, β Leo, β Pic, ɛ Eri and τ Cet", "High-resolution spectroscopy of Vega-like stars - I. Neutron Star Hypothesis for Fomalhaut b 1 A Test of the Neutron Star Hypothesis for Fomalhaut b K. Poppenhaeger,1 ;2? Analysis of existing and new data[19][20] suggests Fomalhaut b is not a planet, rather an expanding dust disk resulting from a former collision. Its estimated surface temperature is 4,711 K and its luminosity only 0.19 L ☉. Following the optical imaging of exoplanet candidate Fomalhaut b (Fom b), we present a numerical model of how Fomalhaut's debris disk is gravitationally shaped by a single interior planet. Effective temperatures, gravities and photospheric abundances", "Anchor Points for the MK System of Spectral Classification", "New HST data and modeling reveal a massive planetesimal collision around Fomalhaut", "Exoplanet Apparently Disappears in Latest Hubble Observations", "Addressing confusion in double star nomenclature: The Washington Multiplicity Catalog", Richard Hinckley Allen: Star Names — Their Lore and Meaning ("Piscis Australis, the Southern Fish", pp. [10][nb 1] A second 1997 study deduced a value of 78%, by assuming Fomalhaut has the same metallicity as the neighboring star TW Piscis Austrini, which has since been argued to be a physical companion. However, its southerly declination is not as great as that of stars such as Acrux, Alpha Centauri and Canopus, meaning that, unlike them, Fomalhaut is visible from a large part of the Northern Hemisphere as well. They published their findings in the journal Science, describing the the massive, young planet as three times the mass of Jupiter. Continuing the line from Beta to Alpha Pegasi towards the southern horizon, Fomalhaut is about 45˚ south of Alpha Pegasi, with no bright stars in between. Infrared non-detections suggest that Fomalhaut b cannot be more massive than 2 times Jupiter's mass[4][18] but a lower limit on the mass depends on uncertain details for the nature of Fomalhaut b, its circumplanetary environment, and the existence of other planetary-mass bodies in the system. [11], Fomalhaut has been claimed to be one of approximately 16 stars belonging to the Castor Moving Group. The nature and even the existence of a putative planet-mass companion (“Fomalhaut b”) to Fomalhaut has been debated since 2008. [22] Under the rules for naming objects in multiple star systems, the three components – Fomalhaut, TW Piscis Austrini and LP 876-10 – are designated A, B and C, respectively. The model is simple, adaptable to other debris disks, and can be extended to accommodate multiple planets. In July 2014, the International Astronomical Union (IAU) launched a process for giving proper names to certain exoplanets. At 40°N, Fomalhaut rises above the horizon for eight hours and reaches only 20° above the horizon, while Capella, which rises at approximately the same time, will stay above the horizon for twenty hours. Some astronomers now say it was a cloud of asteroid debris", "New HST data and modeling reveal a massive planetesimal collision around Fomalhaut", NameExoWorlds: An IAU Worldwide Contest to Name Exoplanets and their Host Stars, Final Results of NameExoWorlds Public Vote Released, Monthly Notices of the Royal Astronomical Society, "Images captured of 4 planets outside solar system", "First pictures taken of planet outside the solar system: Fomalhaut b", "ALMA Reveals Workings of Nearby Planetary System", "New doubts about 'poster child' of exoplanets", "New Study Brings a Doubted Exoplanet 'Back from the Dead, "Fomalhaut b: the first directly observed exoplanet", Hubblecast 22: Hubble directly observes planet orbiting Fomalhaut, NASA's Hubble reveals rogue planetary orbit for Fomalhaut b, https://en.wikipedia.org/w/index.php?title=Fomalhaut_b&oldid=987321158, Short description is different from Wikidata, Creative Commons Attribution-ShareAlike License, This page was last edited on 6 November 2020, at 08:02. 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