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HD 24040 B
HD 24040 b is a long-period exoplanet taking approximately 3500 days to orbit at 4.6 astronomical units in an almost circular orbit. It has a minimum mass 4 times that of Jupiter. Discovery HD 24040b was discovered in 2006 based on observations made at the W. M. Keck Observatory in Hawaii. However, because the observations covered less than one complete orbit there were only weak constraints on the period and mass. The first reliable orbit for HD 24040b was obtained by astronomers at Haute-Provence Observatory in 2012 who combined the keck measurements with ones from the SOPHIE and ELODIE spectrograph ELODIE was an echelle spectrograph installed on the 1.93m reflector at the Observatoire de Haute-Provence in south-eastern France. Its optical instrumentation was developed by André Baranne from the Marseille Observatory. The purpose of the instr ...s. The most recent orbit published in 2015 added additional keck measurements and refined the orbital parameters. References Ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
California, USA
California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the most populated subnational entity in North America and the 34th most populous in the world. The Greater Los Angeles area and the San Francisco Bay Area are the nation's second and fifth most populous urban regions respectively, with the former having more than 18.7million residents and the latter having over 9.6million. Sacramento is the state's capital, while Los Angeles is the most populous city in the state and the second most populous city in the country. San Francisco is the second most densely populated major city in the country. Los Angeles County is the country's most populous, while San Bernardino County is the largest county by area in the country. California borders Oregon to the north, Nevada and Arizona to the east, the M ... [...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] |
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 24040
HD 24040 is a star with two orbiting exoplanets in the equatorial constellation of Taurus. The star is too faint to be viewed with the naked eye, having an apparent visual magnitude of 7.50. Based on parallax measurements, it is located at a distance of 152 light years. However, it is drifting closer to the Sun with a radial velocity of −9.4 km/s. This is a G-type main-sequence star with a stellar classification of G2V. It is a metal-rich star with an age of around 4.8 billion years. The star has 14% more mass than the Sun and 128% of the Sun's radius. It is radiating 1.8 times the luminosity of the Sun from its photosphere at an effective temperature of 5,917 K. The star is spinning slowly with a projected rotational velocity of 2.4 km/s. Planetary system A long period planet was discovered in 2006 based on observations made at the W. M. Keck Observatory in Hawaii. However because the observations covered less than one complete orbit ther ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exoplanet
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] |
Minimum Mass
In astronomy, minimum mass is the lower-bound calculated mass of observed objects such as planets, stars and binary systems, nebulae, and black holes. Minimum mass is a widely cited statistic for extrasolar planets detected by the radial velocity method or Doppler spectroscopy, and is determined using the binary mass function. This method reveals planets by measuring changes in the movement of stars in the line-of-sight, so the real orbital inclinations and true masses of the planets are generally unknown. This is a result of sin ''i'' degeneracy. If inclination ''i'' can be determined, the true mass can be obtained from the calculated minimum mass using the following relationship: M_\text = \frac Exoplanets Orientation of the transit to Earth Most stars will not have their planets lined up and orientated so that they eclipse over the center of the star and give the viewer on earth a perfect transit. It is for this reason that when we often are only able to extrapolate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jupiter
Jupiter is the fifth planet from the Sun and the List of Solar System objects by size, largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, but slightly less than one-thousandth the mass of the Sun. Jupiter is the List of brightest natural objects in the sky, third brightest natural object in the Earth's night sky after the Moon and Venus, and it has been observed since Pre-history, prehistoric times. It was named after the Jupiter (mythology), Roman god Jupiter, the king of the gods. Jupiter is primarily composed of hydrogen, but helium constitutes one-quarter of its mass and one-tenth of its volume. It probably has a rocky core of heavier elements, but, like the other giant planets in the Solar System, it lacks a well-defined solid surface. The ongoing contraction of Jupiter's interior generates more heat than it receives from the Sun. Because of its rapid rotation, the planet' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hawaii
Hawaii ( ; haw, Hawaii or ) is a state in the Western United States, located in the Pacific Ocean about from the U.S. mainland. It is the only U.S. state outside North America, the only state that is an archipelago, and the only state geographically located within the tropics. Hawaii comprises nearly the entire Hawaiian archipelago, 137 volcanic islands spanning that are physiographically and ethnologically part of the Polynesian subregion of Oceania. The state's ocean coastline is consequently the fourth-longest in the U.S., at about . The eight main islands, from northwest to southeast, are Niihau, Kauai, Oahu, Molokai, Lānai, Kahoolawe, Maui, and Hawaii—the last of these, after which the state is named, is often called the "Big Island" or "Hawaii Island" to avoid confusion with the state or archipelago. The uninhabited Northwestern Hawaiian Islands make up most of the Papahānaumokuākea Marine National Monument, the United States' largest protected ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haute-Provence Observatory
The Haute-Provence Observatory (OHP, french: Observatoire de Haute-Provence) is an astronomical observatory in the southeast of France, about 90 km east of Avignon and 100 km north of Marseille. It was established in 1937 as a national facility for French astronomers. Astronomical observations began in 1943 using the 1.20 m telescope, and the first research papers based on observations made at the observatory were published in 1944. Foreign observers first used the observatory in 1949, when Geoffrey and Margaret Burbidge visited. The observatory lies at an altitude of about 650 m, on a plateau near the village of Saint-Michel-l'Observatoire in the Alpes-de-Haute-Provence '' département''. The site was chosen for an observatory because of its generally very favourable observing conditions. On average, 60% of nights are suitable for astronomical observations, with the best seasons are summer and autumn. About 170 nights per year on average are completely cloudless ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SOPHIE échelle Spectrograph
The SOPHIE (Spectrographe pour l’Observation des Phénomènes des Intérieurs stellaires et des Exoplanètes, literally meaning "spectrograph for the observation of the phenomena of the stellar interiors and of the exoplanets") ''échelle spectrograph'' is a high-resolution echelle spectrograph installed on the 1.93m reflector telescope at the Haute-Provence Observatory located in south-eastern France. The purpose of this instrument is asteroseismology and extrasolar planet detection by the radial velocity method. It builds upon and replaces the older ELODIE spectrograph. This instrument was made available for use by the general astronomical community October 2006. Characteristics The electromagnetic spectrum wavelength range is from 387.2 to 694.3 nanometers. The spectrograph is fed from the Cassegrain focus through either one of two separate optical fiber sets, yielding two different spectral resolutions (HE and HR modes). The instrument is entirely computer-controlled. A stand ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ELODIE Spectrograph
ELODIE was an echelle spectrograph installed on the 1.93m reflector at the Observatoire de Haute-Provence in south-eastern France. Its optical instrumentation was developed by André Baranne from the Marseille Observatory. The purpose of the instrument was extrasolar planet detection by the radial velocity method. ELODIE's first light was achieved in 1993. The instrument was decommissioned in August 2006 and replaced in September 2006 by SOPHIE, a new instrument of the same type but with improved features. Characteristics The instrument could observe the electromagnetic spectrum over a wavelength range of 389.5 nm to 681.5 nm in a single exposure, split into 67 spectral orders. The instrument, which was located in a temperature-controlled room, was fed with optical fibers from the Cassegrain focus. The observatory provided an integrated data reduction pipeline which fully reduced the spectra immediately after acquisition and allowed the user to measure radial velociti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Giant Planets
The giant planets constitute a diverse type of planet much larger than Earth. They 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 known giant planets in the Solar System: Jupiter, Saturn, Uranus and Neptune. Many extrasolar giant planets have been identified orbiting other stars. They are also sometimes called jovian planets, after Jupiter ("Jove" being another name for the Roman god "Jupiter"). They are also sometimes known as gas giants. However, many astronomers now apply the latter term only to Jupiter and Saturn, classifying Uranus and Neptune, which have different compositions, as ice giants. Both names are potentially misleading: all of the giant planets consist primarily of fluids above their critical points, where distinct gas and liquid phases do not exist. The principal components are hydrogen and helium in the case of Jupiter and Saturn, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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