Gliese 504 b (or 59 Virginis b ) is a Jovian planet or brown dwarf located in the system of the solar analog 59 Virginis (GJ 504) , discovered by direct imaging using HiCIAO instrument and AO188 adaptive optics system on the Subaru Telescope of Mauna Kea Observatory , Hawaii by Kuzuhara et al.
26-541: The discovery images were taken in 2011 and common proper motion was confirmed in 2012 as part of the Strategic Explorations of Exoplanets and Disks with Subaru (SEEDS) survey. The SEEDS survey aims to detect and characterize giant planets and circumstellar disks using the 8.2-meter Subaru Telescope . In February 2013 Kuzuhara et al. submitted the discovery paper to The Astrophysical Journal , and in September it
52-407: A star system tend to be small fractions of a light-year, and are usually expressed in astronomical units . However, smaller units of length can similarly be formed usefully by multiplying units of time by the speed of light. For example, the light-second , useful in astronomy, telecommunications and relativistic physics, is exactly 299 792 458 metres or 1 / 31 557 600 of
78-473: A unit of time . The light-year is most often used when expressing distances to stars and other distances on a galactic scale, especially in non-specialist contexts and popular science publications. The unit most commonly used in professional astronomy is the parsec (symbol: pc, about 3.26 light-years). As defined by the International Astronomical Union (IAU), the light-year
104-440: A Sun-like star named GJ 504 . The projected distance from the central star is 44 AU at a distance of 59 light years. The central star itself is bright, visible to the naked-eye (V ~ 5 mag), but the planet is very dim, 17–20 mag at infrared wavelengths. The planet mass is estimated to be only 3–4.5 Jupiter masses, estimated from its luminosity and age. It is one of the lightest-mass planets ever imaged. The survey also discovered
130-412: A light-year. Units such as the light-minute, light-hour and light-day are sometimes used in popular science publications. The light-month, roughly one-twelfth of a light-year, is also used occasionally for approximate measures. The Hayden Planetarium specifies the light month more precisely as 30 days of light travel time. Light travels approximately one foot in a nanosecond ; the term "light-foot"
156-589: A likely superjovian-mass planet named Kappa Andromedae b , orbiting a young B-type star 2.8 times the mass of Sun. HD 100546 b was confirmed as a planet with a disk system around a very young star as part of the SEEDS survey. SEEDS has also reported the detection of three brown dwarfs in the Pleiades cluster as part of the Open Cluster category survey and several stellar or substellar companions around planetary systems, from
182-548: Is "ly", International standards like ISO 80000:2006 (now superseded) have used "l.y." and localized abbreviations are frequent, such as "al" in French, Spanish, and Italian (from année-lumière , año luz and anno luce , respectively), "Lj" in German (from Lichtjahr ), etc. Before 1984, the tropical year (not the Julian year) and a measured (not defined) speed of light were included in
208-448: Is 544±10 К (271±10 °C), much cooler than previously imaged exoplanets with a clear planetary origin. The angular separation of the planet from its parent star is about 2.5 arcseconds , corresponding to a projected separation of 43.5 AU , which is nearly nine times the distance between Jupiter and the Sun, which poses a challenge to theoretical ideas of how giant planets form. This planet
234-402: Is a unit of length used to express astronomical distances and is equal to exactly 9 460 730 472 580 .8 km , which is approximately 5.88 trillion mi. As defined by the International Astronomical Union (IAU), a light-year is the distance that light travels in vacuum in one Julian year (365.25 days). Despite its inclusion of the word "year", the term should not be misinterpreted as
260-723: Is a multi-year survey that used the Subaru Telescope on Mauna Kea, Hawaii in an effort to directly image extrasolar planets and protoplanetary / debris disks around hundreds of nearby stars. SEEDS is a Japanese-led international project. It consists of some 120 researchers from a number of institutions in Japan, the U.S. and the EU. The survey's headquarters is at the National Astronomical Observatory of Japan (NAOJ) and led by Principal Investigator Motohide Tamura. The goals of
286-528: Is an odd name. In 1868 an English journal labelled the light-year as a unit used by the Germans. Eddington called the light-year an inconvenient and irrelevant unit, which had sometimes crept from popular use into technical investigations. Although modern astronomers often prefer to use the parsec , light-years are also popularly used to gauge the expanses of interstellar and intergalactic space. Distances expressed in light-years include those between stars in
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#1732852801200312-462: Is seen as an excellent target for detailed spectroscopic characterization due to its proximity to Earth and its wide separation. Estimated mass of Gliese 504 b depends on the value of its age, which is poorly known. The discoverers adopted age value 0.16 −0.06 Gyr and estimated mass as 4.0 −1.0 M Jup . In 2015, other astronomers obtained age value 4.5 −1.5 Gyr, which corresponds to 20-30 M Jup . In this case,
338-560: Is the product of the Julian year (365.25 days, as opposed to the 365.2425-day Gregorian year or the 365.24219-day Tropical year that both approximate) and the speed of light ( 299 792 458 m/s ). Both of these values are included in the IAU (1976) System of Astronomical Constants , used since 1984. From this, the following conversions can be derived: The abbreviation used by the IAU for light-year
364-545: Is the product of the J1900.0 mean tropical year and the defined speed of light. Abbreviations used for light-years and multiples of light-years are: The light-year unit appeared a few years after the first successful measurement of the distance to a star other than the Sun, by Friedrich Bessel in 1838. The star was 61 Cygni , and he used a 160-millimetre (6.2 in) heliometre designed by Joseph von Fraunhofer . The largest unit for expressing distances across space at that time
390-541: The radial velocity detection. SEEDS has detected interesting fine-structures in disks around dozens of young stars. These disks exhibit gaps, spiral arms, rings, and other structures at similar radial distances where the outer planets are imaged. These structures can be considered to be "signposts" of planets. The results obtained on disks support the need for a new planet formation model. Additional planet and disk discoveries include: Light-year A light-year , alternatively spelled light year ( ly or lyr ),
416-496: The IAU (1964) System of Astronomical Constants, used from 1968 to 1983. The product of Simon Newcomb 's J1900.0 mean tropical year of 31 556 925 .9747 ephemeris seconds and a speed of light of 299 792 .5 km/s produced a light-year of 9.460 530 × 10 m (rounded to the seven significant digits in the speed of light) found in several modern sources was probably derived from an old source such as C. W. Allen 's 1973 Astrophysical Quantities reference work, which
442-464: The large Subaru 8.2 m telescope, including a second-generation adaptive optics (AO) system with 188 actuators (AO188) and a dedicated coronagraph instrument called HiCIAO. Observations began in late October 2009 and were completed in early January 2015, having observed roughly 500 nearby stars (including duplicates). The survey was conducted in the H-band (1.65 micron) and once a planet/companion candidate
468-438: The mental picture of the approximate transit time for light, but he refrained from using the light-year as a unit. He may have resisted expressing distances in light-years because it would reduce the accuracy of his parallax data due to multiplying with the uncertain parameter of the speed of light. The speed of light was not yet precisely known in 1838; the estimate of its value changed in 1849 ( Fizeau ) and 1862 ( Foucault ). It
494-529: The object is a brown dwarf rather than a planet. In 2017, an intermediate age value 2.5 −0.7 Gyr was published, while in 2018 two ages of 21 ± 2 Myr and 4 ± 1.8 Gyr were published, corresponding to planetary masses of 1.3 +0.6 −0.3 M J and 23 +10 −9 M J respectively. Radius of Gliese 504 b is estimated as 0.96 ± 0.07 R J . Strategic Explorations of Exoplanets and Disks with Subaru Strategic Explorations of Exoplanets and Disks with Subaru (SEEDS)
520-485: The same general area, such as those belonging to the same spiral arm or globular cluster . Galaxies themselves span from a few thousand to a few hundred thousand light-years in diameter, and are separated from neighbouring galaxies and galaxy clusters by millions of light-years. Distances to objects such as quasars and the Sloan Great Wall run up into the billions of light-years. Distances between objects within
546-400: The survey are to address the following key issues in the study of extrasolar planets and disks: the detection and census of exoplanets in the regions around solar-mass and massive stars; the evolution of protoplanetary disks and debris disks ; and the link between exoplanets and circumstellar disks . The direct imaging survey was carried out with a suite of high-contrast instrumentation at
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#1732852801200572-404: Was detected, it was also observed at other near-infrared wavelengths. SEEDS has reported four candidate planets to date. The first one is GJ 758 b , with a mass around 10–30 Jupiter masses and orbiting around a Sun-like star. The projected distance from the central star to the companion is 29 AU at a distance of around 52 light years . The second discovery was of a very faint planet orbiting
598-432: Was not yet considered to be a fundamental constant of nature, and the propagation of light through the aether or space was still enigmatic. The light-year unit appeared in 1851 in a German popular astronomical article by Otto Ule . Ule explained the oddity of a distance unit name ending in "year" by comparing it to a walking hour ( Wegstunde ). A contemporary German popular astronomical book also noticed that light-year
624-536: Was published. A follow-up study published in the October 2013 edition of the Astrophysical Journal confirmed methane absorption in the infrared H band, the first time this has been done for a directly imaged planet that formed within a disk. GJ 504 b's spectral type was originally projected to be late T or early Y, and a follow-up study estimated that a T8 spectral type was the best fit. Its effective temperature
650-488: Was the astronomical unit , equal to the radius of the Earth's orbit at 150 million kilometres (93 million miles). In those terms, trigonometric calculations based on 61 Cygni's parallax of 0.314 arcseconds, showed the distance to the star to be 660 000 astronomical units (9.9 × 10 km; 6.1 × 10 mi). Bessel added that light takes 10.3 years to traverse this distance. He recognized that his readers would enjoy
676-438: Was updated in 2000, including the IAU (1976) value cited above (truncated to 10 significant digits). Other high-precision values are not derived from a coherent IAU system. A value of 9.460 536 207 × 10 m found in some modern sources is the product of a mean Gregorian year (365.2425 days or 31 556 952 s ) and the defined speed of light ( 299 792 458 m/s ). Another value, 9.460 528 405 × 10 m ,
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