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Kepler-102d
Kepler-102 is a star in the constellation of Lyra. Kepler-102 is less luminous than the Sun. The star system does not contain any observable amount of dust. Kepler-102 is suspected to be orbited by a binary consisting of two red dwarf stars, at projected separations of 591 and 627 AU. Planetary system In January 2014, a system of five planets around the star was announced, three of them being smaller than Earth. While 3 of the transit signals were discovered during the first year of the Kepler mission, their small size made them hard to confirm as possibilities of these being false positives were needed to be removed. Later, two other signals were detected. Follow-up radial velocity data helped to determine the mass of the largest planet (Kepler-102e). In 2017, the search for additional planets utilizing Transit-timing variation method has yielded zero results, although presence of planets with semimajor axis beyond 10 AU cannot be excluded. See also * Copernic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lyra
Lyra (; Latin for lyre, from Greek ''λύρα'') is a small constellation. It is one of the 48 listed by the 2nd century astronomer Ptolemy, and is one of the modern 88 constellations recognized by the International Astronomical Union. Lyra was often represented on star maps as a vulture or an eagle carrying a lyre, and hence is sometimes referred to as Vultur Cadens or Aquila Cadens ("Falling Vulture" or "Falling Eagle"), respectively. Beginning at the north, Lyra is bordered by Draco, Hercules, Vulpecula, and Cygnus. Lyra is nearly overhead in temperate northern latitudes shortly after midnight at the start of summer. From the equator to about the 40th parallel south it is visible low in the northern sky during the same (thus winter) months. Vega, Lyra's brightest star, is one of the brightest stars in the night sky, and forms a corner of the famed Summer Triangle asterism. Beta Lyrae is the prototype of a class of binary stars known as Beta Lyrae variables. These bi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Constellation
A constellation is an area on the celestial sphere in which a group of visible stars forms a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object. The origins of the earliest constellations likely go back to prehistory. People used them to relate stories of their beliefs, experiences, creation, or mythology. Different cultures and countries adopted their own constellations, some of which lasted into the early 20th century before today's constellations were internationally recognized. The recognition of constellations has changed significantly over time. Many changed in size or shape. Some became popular, only to drop into obscurity. Some were limited to a single culture or nation. The 48 traditional Western constellations are Greek. They are given in Aratus' work ''Phenomena'' and Ptolemy's '' Almagest'', though their origin probably predates these works by several centuries. Constellations in the far southern sky were ad ... [...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 astronomic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kepler (spacecraft)
The Kepler space telescope is a disused space telescope launched by NASA in 2009 to discover Earth-sized planets orbiting other stars. Named after astronomer Johannes Kepler, the spacecraft was launched into an Earth-trailing heliocentric orbit. The principal investigator was William J. Borucki. After nine and a half years of operation, the telescope's reaction control system fuel was depleted, and NASA announced its retirement on October 30, 2018. Designed to survey a portion of Earth's region of the Milky Way to discover Earth-size exoplanets in or near habitable zones and estimate how many of the billions of stars in the Milky Way have such planets, Kepler's sole scientific instrument is a photometer that continually monitored the brightness of approximately 150,000 main sequence stars in a fixed field of view. These data were transmitted to Earth, then analyzed to detect periodic dimming caused by exoplanets that cross in front of their host star. Only planets whose or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kepler-102e
Kepler-102 is a star in the constellation of Lyra. Kepler-102 is less luminous than the Sun. The star system does not contain any observable amount of dust. Kepler-102 is suspected to be orbited by a binary consisting of two red dwarf stars, at projected separations of 591 and 627 AU. Planetary system In January 2014, a system of five planets around the star was announced, three of them being smaller than Earth. While 3 of the transit signals were discovered during the first year of the Kepler mission, their small size made them hard to confirm as possibilities of these being false positives were needed to be removed. Later, two other signals were detected. Follow-up radial velocity data helped to determine the mass of the largest planet ( Kepler-102e). In 2017, the search for additional planets utilizing Transit-timing variation method has yielded zero results, although presence of planets with semimajor axis beyond 10 AU cannot be excluded. See also * Coperni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transit-timing Variation
Transit-timing variation is a method for detecting exoplanets by observing variations in the timing of a transit. This provides an extremely sensitive method capable of detecting additional planets in the system with masses potentially as small as that of Earth. In tightly packed planetary systems, the gravitational pull of the planets among themselves causes one planet to accelerate and another planet to decelerate along its orbit. The acceleration causes the orbital period of each planet to change. Detecting this effect by measuring the change is known as transit-timing variations. "Timing variation" asks whether the transit occurs with strict periodicity or if there's a variation. The first significant detection of a non-transiting planet using transit-timing variations was carried out with NASA's Kepler telescope. The transiting planet Kepler-19b shows transit-timing variation with an amplitude of 5 minutes and a period of about 300 days, indicating the presence of a second ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
55 Cancri
55 Cancri is a binary star system located 41 light-years away from the Sun in the zodiac constellation of Cancer. It has the Bayer designation Rho1 Cancri (ρ1 Cancri); ''55 Cancri'' is the Flamsteed designation (abbreviated 55 Cnc). The system consists of a K-type star (designated 55 Cancri A, also named Copernicus ) and a smaller red dwarf (55 Cancri B). , five extrasolar planets (designated 55 Cancri b, c, d, e and f; named Galileo, Brahe, Lipperhey, Janssen and Harriot, respectively) are known to orbit 55 Cancri A. Nomenclature 55 Cancri is the system's Flamsteed designation. It also bears the Bayer designation ρ1 Cancri ( Latinised to Rho1 Cancri) and the Bright Star Catalogue designation HR 3522. The two components are designated A and B, though component A is sometimes referred to simply as 55 Cancri. The first planet discovered orbiting 55 Cancri A was designated HR 3522b by its discoverers, though it is more commonly referred to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kepler-37
Kepler-37, also known as UGA-1785, is a G-type main-sequence star located in the constellation Lyra 209 light years from Earth. It is host to Extrasolar planet, exoplanets Kepler-37b, Kepler-37c, Kepler-37d and Kepler-37e, all of which orbit very close to it. Kepler-37 has a mass about 80.3 percent of the Sun's and a radius about 77 percent as large. It has a temperature similar to that of the Sun, but a bit cooler at 5,417 Kelvin, K. It has about half the metallicity of the Sun. With an age of roughly 6 billion years, it is slightly older than the Sun, but is still a main-sequence star. Until January 2015, Kepler-37 was the smallest star to be measured via asteroseismology. Planetary system Kepler-37b is the closest planet to the Kepler-37. At the time of its discovery in February 2013, it was the smallest known exoplanet. At in diameter, it is slightly larger than the Moon. It orbits Kepler-37 once every 13 days at a distance of about 0.1 astronomical units (A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kepler-20
Kepler-20 is a star 929 light-years from Earth in the constellation Lyra with a system of six known planets. The apparent magnitude of this star is 12.51, so it cannot be seen with the unaided eye. Viewing it requires a telescope with an aperture of or more. It is slightly smaller than the Sun, with 94% of the Sun's radius and about 91% of the Sun's mass. The effective temperature of the photosphere is slightly cooler than that of the Sun at , giving it the characteristic yellow hue of a stellar class G8 star. The abundance of elements other than hydrogen or helium, what astronomers term the metallicity, is approximately the same as in the Sun. It may be older than the Sun, although the margin of error here is relatively large. Planetary system On December 20, 2011, the Kepler Space Telescope team reported the discovery of a five-planet system containing three small gas giants and the first two Earth-sized extrasolar planets, Kepler-20e (the first known extrasolar plane ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kepler-33
Kepler-33 is a star in the constellation of Cygnus with a system of five known planets. Having just begun to evolve off from the main sequence, its radius and mass are difficult to ascertain, although data available in 2020 shows its best-fit mass of 1.3 and diameter of 1.6 are compatible with a model of a subgiant star. Planetary system First detections of the four-body planetary system were reported in February 2011. On January 26, 2012, a 5th planet around the star was confirmed. However, unlike other planets confirmed via Kepler, their masses were initially not known, as Doppler Spectroscopy measurements were not done before the announcement. Judging by their radii, b may be a large Super-Earth or small Hot Neptune while the other four are all likely to be the latter. Planets b and c may actually be in a 7:3 resonance, as there is a 0.05 day discrepancy; there is also a small 0.18 day discrepancy between a 5:3 resonance between planets c and d. The other planets do n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lyra (constellation)
Lyra (; Latin for lyre, from Greek ''λύρα'') is a small constellation. It is one of the 48 listed by the 2nd century astronomer Ptolemy, and is one of the modern 88 constellations recognized by the International Astronomical Union. Lyra was often represented on star maps as a vulture or an eagle carrying a lyre, and hence is sometimes referred to as Vultur Cadens or Aquila Cadens ("Falling Vulture" or "Falling Eagle"), respectively. Beginning at the north, Lyra is bordered by Draco, Hercules, Vulpecula, and Cygnus. Lyra is nearly overhead in temperate northern latitudes shortly after midnight at the start of summer. From the equator to about the 40th parallel south it is visible low in the northern sky during the same (thus winter) months. Vega, Lyra's brightest star, is one of the brightest stars in the night sky, and forms a corner of the famed Summer Triangle asterism. Beta Lyrae is the prototype of a class of binary stars known as Beta Lyrae variables. These binary st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kepler Objects Of Interest
Johannes Kepler (; ; 27 December 1571 – 15 November 1630) was a German astronomer, mathematician, astrologer, natural philosopher and writer on music. He is a key figure in the 17th-century Scientific Revolution, best known for his laws of planetary motion, and his books ''Astronomia nova'', ''Harmonice Mundi'', and ''Epitome Astronomiae Copernicanae''. These works also provided one of the foundations for Newton's theory of universal gravitation. Kepler was a mathematics teacher at a seminary school in Graz, where he became an associate of Prince Hans Ulrich von Eggenberg. Later he became an assistant to the astronomer Tycho Brahe in Prague, and eventually the imperial mathematician to Emperor Rudolf II and his two successors Matthias and Ferdinand II. He also taught mathematics in Linz, and was an adviser to General Wallenstein. Additionally, he did fundamental work in the field of optics, invented an improved version of the refracting (or Keplerian) telescope, and w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
