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HD 109749 B
HD 109749 b is an extrasolar planet that takes only 5.24 days to orbit the star HD 109749 at a distance of 0.063 AU. It was discovered on August 22, 2005, the same day as Gliese 581 b. See also * HD 149143 b HD 149143 b, formally named Riosar, is an extrasolar planet that has a minimum mass of 1.33 Jupiter masses. As is typical for a lot of hot Jupiters, its orbital eccentricity is low. Naming Project The star HD 149143 and its orbiting planet HD 1 ... References External links * Hot Jupiters Exoplanets discovered in 2005 Giant planets Centaurus Exoplanets detected by radial velocity {{extrasolar-planet-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Debra Fischer
Debra Ann Fischer is a professor of astronomy at Yale University researching detection and characterization of exoplanets. She was part of the team to discover the first known multiple-planet system. Education Fischer received her degree from the University of Iowa in 1975, a masters of science from San Francisco State University in 1992, and her PhD from the University of California at Santa Cruz in 1998. Research and career Fischer has co-authored over 100 papers on dwarf stars and sub-stellar mass objects in the galactic neighborhood, including many on extrasolar planets. Her work "The Twenty Five Year Lick Planet Search" is summarized in a paper by Fischer, Marcy & Spronck 2014. She is a principal investigator with the N2K Consortium searching for exoplanets. She co-leads the planet search team with Gregory P. Laughlin and Jessi Cisewski looking for extrasolar planets. She was the primary investigator for Chiron, the CTIO High Resolution Spectrometer. In 2011, she sta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Keck Observatory
The W. M. Keck Observatory is an astronomical observatory with two telescopes at an elevation of 4,145 meters (13,600 ft) near the summit of Mauna Kea in the U.S. state of Hawaii. Both telescopes have aperture primary mirrors, and when completed in 1993 (Keck 1) and 1996 (Keck 2) were the largest astronomical telescopes in the world. They are currently the 3rd and 4th largest. Overview With a concept first proposed in 1977, telescope designers at the University of California, Berkeley (Terry Mast) and Lawrence Berkeley Laboratory (Jerry Nelson) had been developing the technology necessary to build a large, ground-based telescope. With a design in hand, a search for the funding began. In 1985, Howard B. Keck of the W. M. Keck Foundation gave $70 million to fund the construction of the Keck I telescope, which began in September 1985, with first light occurring on 24 November 1990 using nine of the eventual 36 segments. With construction of the first telescope well ad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Doppler Spectroscopy
Doppler spectroscopy (also known as the radial-velocity method, or colloquially, the wobble method) is an indirect method for finding extrasolar planets and brown dwarfs from radial-velocity measurements via observation of Doppler shifts in the spectrum of the planet's parent star. 1,018 extrasolar planets (about 19.5% of the total) have been discovered using Doppler spectroscopy, as of November 2022. History Otto Struve proposed in 1952 the use of powerful spectrographs to detect distant planets. He described how a very large planet, as large as Jupiter, for example, would cause its parent star to wobble slightly as the two objects orbit around their center of mass. He predicted that the small Doppler shifts to the light emitted by the star, caused by its continuously varying radial velocity, would be detectable by the most sensitive spectrographs as tiny redshifts and blueshifts in the star's emission. However, the technology of the time produced radial-velocity meas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
N2K Consortium
The N2K Consortium is a collaborative multinational effort by United States, American, Chilean and Japanese astronomers to find additional extrasolar planets around stars that are not already being surveyed. The N2K is shorthand for the set of roughly 2,000 of the nearest and most luminous main sequence stars that were selected to be newly surveyed. Target stars have a B - V color index value between 0.4 and 1.2, a visual magnitude brighter than 10.5, and a distance of less than 110 parsec, pc from the Sun. They were selected based upon their high metallicity, which is the abundance of elements other than hydrogen and helium. The observing campaign uses the W. M. Keck Observatory, Keck, Magellan Telescopes, Magellan and Subaru Telescope, Subaru telescopes, plus automated telescopes at Fairborn Observatory. Each star is observed three times over a period of several days, then checked for short period variations in radial velocity. This variation is a characteristic of gravitation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astronomical Unit
The astronomical unit (symbol: au, or or AU) is a unit of length, roughly the distance from Earth to the Sun and approximately equal to or 8.3 light-minutes. The actual distance from Earth to the Sun varies by about 3% as Earth orbits the Sun, from a maximum (aphelion) to a minimum (perihelion) and back again once each year. The astronomical unit was originally conceived as the average of Earth's aphelion and perihelion; however, since 2012 it has been defined as exactly (see below for several conversions). The astronomical unit is used primarily for measuring distances within the Solar System or around other stars. It is also a fundamental component in the definition of another unit of astronomical length, the parsec. History of symbol usage A variety of unit symbols and abbreviations have been in use for the astronomical unit. In a 1976 resolution, the International Astronomical Union (IAU) had used the symbol ''A'' to denote a length equal to the astronomical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HD 109749
HD 109749 is a binary star system about 206 light years away in the constellation of Centaurus. The pair have a combined apparent visual magnitude of 8.08, which is too faint to be visible to the naked eye. The primary component has a close orbiting exoplanet companion. The system is drifting closer with a heliocentric radial velocity of −13.2 km/s. The primary component, HD 109749 A, is a G-type subgiant star with a spectral type of G3IV, indicating it is an evolved star with a luminosity higher than that of a main sequence star. It has a mass of and a radius of . The star is shining with a luminosity of and has an effective temperature of 5,860 K. Evolutionary models estimate an age of 4.1 billion years. HD 109749 A is chromospherically inactive and has a high metallicity, with an iron abundance 178% of Sun's. The secondary, HD 109749 B, is a K-type main sequence star with an apparent magnitude of 10.3. It has a mass of about and is located at a separ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extrasolar Planet
An exoplanet or extrasolar planet is a planet outside the Solar System. The first possible evidence of an exoplanet was noted in 1917 but was not recognized as such. The first confirmation of detection occurred in 1992. A different planet, initially detected in 1988, was confirmed in 2003. There are many methods of detecting exoplanets. Transit (astronomy), Transit photometry and Doppler spectroscopy have found the most, but these methods suffer from a clear observational bias favoring the detection of planets near the star; thus, 85% of the exoplanets detected are inside the tidal locking zone. In several cases, List of multiplanetary systems, multiple planets have been observed around a star. About 1 in 5 Solar analog, Sun-like starsFor the purpose of this 1 in 5 statistic, "Sun-like" means G-type star. Data for Sun-like stars was not available so this statistic is an extrapolation from data about K-type star, K-type stars. have an "Earth-sized"For the purpose of this 1 in 5 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Star
A star is an astronomical object comprising a luminous spheroid of plasma (physics), plasma held together by its gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night sky, night, but their immense distances from Earth make them appear as fixed stars, fixed points of light. The most prominent stars have been categorised into constellations and asterism (astronomy), asterisms, and many of the brightest stars have proper names. Astronomers have assembled star catalogues that identify the known stars and provide standardized stellar designations. The observable universe contains an estimated to stars. Only about 4,000 of these stars are visible to the naked eye, all within the Milky Way galaxy. A star's life star formation, begins with the gravitational collapse of a gaseous nebula of material composed primarily of hydrogen, along with helium and trace amounts of heavier elements. Its stellar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gliese 581 B
Gliese 581b or Gl 581b is an extrasolar planet orbiting within the Gliese 581 system. It is the first planet discovered of three confirmed in the system so far, and the second in order from the star. Discovery The planet was discovered by a team of French and Swiss astronomers, who announced their findings on November 30, 2005, as a discovery of one of the smallest extrasolar planets ever found, with one conclusion being that planets may be more common around the smallest stars. It was the fifth planet found around a red dwarf star (after Gliese 876's planets and Gliese 436, Gliese 436 b). The planet was discovered using the HARPS instrument, with which they found the host star to have a wobble that implied the existence of the planet. The astronomers published their results in ''Astronomy and Astrophysics Letters''. Orbit and mass Gliese 581b is at a minimum, approximately 15.8 times the Earth's mass, similar to Neptune's mass. It does not transit its star, implying that it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HD 149143 B
HD 149143 b, formally named Riosar, is an extrasolar planet that has a minimum mass of 1.33 Jupiter masses. As is typical for a lot of hot Jupiters, its orbital eccentricity is low. Naming Project The star HD 149143 HD 149143, formally named Rosalíadecastro, is a star located in the Ophiuchus constellation that has spectral type of G0 located at a distance of 240 light-years from us. Its apparent magnitude is 7.9 (a binocular object) and the absolute ... and its orbiting planet HD 149143 b have been assigned to be named by Spain in 2019's IAU100 NameExoWorlds project. On December 17, 2019, by majority vote in the Spanish Astronomical Association, HD 149143 was given the name Rosalíadecastro in honour of the Spanish poet Rosalía de Castro, who was a significant figure of Galician culture and prominent Spanish writer, whose pioneering work often referenced the night and celestial objects. The planet that orbits it, HD 149143 b, was assigned the name Riosar in honou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hot Jupiters
Hot Jupiters (sometimes called hot Saturns) are a class of gas giant exoplanets that are inferred to be physically similar to Jupiter but that have very short orbital periods (). The close proximity to their stars and high surface-atmosphere temperatures resulted in their informal name "hot Jupiters". Hot Jupiters are the easiest extrasolar planets to detect via the radial-velocity method, because the oscillations they induce in their parent stars' motion are relatively large and rapid compared to those of other known types of planets. One of the best-known hot Jupiters is . Discovered in 1995, it was the first extrasolar planet found orbiting a Sun-like star. has an orbital period of about 4 days. General characteristics Though there is diversity among hot Jupiters, they do share some common properties. * Their defining characteristics are their large masses and short orbital periods, spanning 0.36–11.8 Jupiter masses and 1.3–111 Earth days. The mass ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exoplanets Discovered In 2005
An exoplanet or extrasolar planet is a planet outside the Solar System. The first possible evidence of an exoplanet was noted in 1917 but was not recognized as such. The first confirmation of detection occurred in 1992. A different planet, initially detected in 1988, was confirmed in 2003. There are many methods of detecting exoplanets. Transit photometry and Doppler spectroscopy have found the most, but these methods suffer from a clear observational bias favoring the detection of planets near the star; thus, 85% of the exoplanets detected are inside the tidal locking zone. In several cases, multiple planets have been observed around a star. About 1 in 5 Sun-like starsFor the purpose of this 1 in 5 statistic, "Sun-like" means G-type star. Data for Sun-like stars was not available so this statistic is an extrapolation from data about K-type stars. have an "Earth-sized"For the purpose of this 1 in 5 statistic, Earth-sized means 1–2 Earth radii. planet in the habitable zone. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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