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Microlensing Observations In Astrophysics
Microlensing Observations in Astrophysics (MOA) is a collaborative project between researchers in New Zealand and Japan, led by Professor Yasushi Muraki of Nagoya University. They use microlensing to observe dark matter, extra-solar planets, and stellar atmospheres from the Southern Hemisphere. The group concentrates especially on the detection and observation of gravitational microlensing events of high magnification, of order 100 or more, as these provide the greatest sensitivity to extrasolar planets. They work with other groups in Australia, the United States and elsewhere. Observations are conducted at New Zealand's Mt. John University Observatory using a reflector telescope built for the project. In September 2020, astronomers using microlensing techniques reported the detection, for the first time, of an earth-mass rogue planet unbounded by any star, and free floating in the Milky Way galaxy. In January 2022 in collaboration with Optical Gravitational Lensing Ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dome For MOA Telescope
A dome () is an architectural element similar to the hollow upper half of a sphere. There is significant overlap with the term cupola, which may also refer to a dome or a structure on top of a dome. The precise definition of a dome has been a matter of controversy and there are a wide variety of forms and specialized terms to describe them. A dome can rest directly upon a rotunda wall, a drum, or a system of squinches or pendentives used to accommodate the transition in shape from a rectangular or square space to the round or polygonal base of the dome. The dome's apex may be closed or may be open in the form of an oculus, which may itself be covered with a roof lantern and cupola. Domes have a long architectural lineage that extends back into prehistory. Domes were built in ancient Mesopotamia, and they have been found in Persian, Hellenistic, Roman, and Chinese architecture in the ancient world, as well as among a number of indigenous building traditions throughout the w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terrestrial Planet
A terrestrial planet, telluric planet, or rocky planet, is a planet that is composed primarily of silicate rocks or metals. Within the Solar System, the terrestrial planets accepted by the IAU are the inner planets closest to the Sun: Mercury, Venus, Earth and Mars. Among astronomers who use the geophysical definition of a planet, two or three planetary-mass satellites – Earth's Moon, Io, and sometimes Europa – may also be considered terrestrial planets; and so may be the rocky protoplanet-asteroids Pallas and Vesta.Emily Lakdawalla et al.What Is A Planet?The Planetary Society, 21 April 2020 The terms "terrestrial planet" and "telluric planet" are derived from Latin words for Earth (''Terra'' and ''Tellus''), as these planets are, in terms of structure, ''Earth-like''. Terrestrial planets are generally studied by geologists, astronomers, and geophysicists. Terrestrial planets have a solid planetary surface, making them substantially different from the larger gaseou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MOA-2007-BLG-192Lb
MOA-2007-BLG-192Lb, occasionally shortened to MOA-192 b, , . Accessed on line July 2, 2008. is an approximately 3,000 s away in the constellation of Sagittarius. The planet was discovered orbiting the |
MOA-2007-BLG-400Lb
MOA-2007-BLG-400Lb is an extrasolar planet located approximately 20000 light-years away in the constellation of Sagittarius, orbiting the star MOA-2007-BLG-400L. This planet was detected on September 18, 2008 by the gravitational microlensing by Dong. It has mass between 50% to 130% of Jupiter Jupiter is the fifth planet from the Sun and the 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 th ... and orbits between 0.6 and 1.1 AU. References web preprint External links * Exoplanets discovered in 2008 Sagittarius (constellation) Giant planets Exoplanets detected by microlensing {{extrasolar-planet-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MOA-2009-BLG-387L
MOA-2009-BLG-387L is a red dwarf in the Sagittarius constellation that is host to the planet MOA-2009-BLG-387Lb. The star is estimated to be nearly 20,000 light years away and approximately one fifth the mass of the Sun, although large confidence intervals exist, reflecting the uncertainties in both the mass and distance. The star drew the attention of astronomers when it became the lens of gravitational microlensing event MOA-2009-BLG-387L, in which it eclipsed a background star and created distorted caustics, an envelope of reflected or refracted light rays. Analysis of the caustic events and of follow-up observational data led to the planet's discovery, which was reported in February 2011. Observational history On July 24, 2009, the Microlensing Observations in Astrophysics collaboration (MOA) detected the star MOA-2009-BLG-387L eclipsing a background star in a microlensing event that was named MOA-2009-BLG-387. In a process called gravitational microlensing, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MOA-2007-BLG-197Lb
MOA-2007-BLG-197Lb is a brown dwarf discovered in August 2015 by the MOA Moa are extinct giant flightless birds native to New Zealand. The term has also come to be used for chicken in many Polynesian cultures and is found in the names of many chicken recipes, such as Kale moa and Moa Samoa. Moa or MOA may also refe ... collaboration. It is the first brown dwarf found by the microlensing method to orbit a solar-type star. References Exoplanets discovered in 2015 Exoplanets detected by microlensing Brown dwarfs {{Brown-dwarf-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Planet
A planet is a large, rounded astronomical body that is neither a star nor its remnant. The best available theory of planet formation is the nebular hypothesis, which posits that an interstellar cloud collapses out of a nebula to create a young protostar orbited by a protoplanetary disk. Planets grow in this disk by the gradual accumulation of material driven by gravity, a process called accretion. The Solar System has at least eight planets: the terrestrial planets Mercury, Venus, Earth and Mars, and the giant planets Jupiter, Saturn, Uranus and Neptune. These planets each rotate around an axis tilted with respect to its orbital pole. All of them possess an atmosphere, although that of Mercury is tenuous, and some share such features as ice caps, seasons, volcanism, hurricanes, tectonics, and even hydrology. Apart from Venus and Mars, the Solar System planets generate magnetic fields, and all except Venus and Mercury have natural satellites. The giant planets ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rogue Black Hole
A rogue black hole (also termed a free-floating, interstellar, nomad, orphan, unbound or wandering black hole) is an interstellar object without a host galactic group. They are caused by collisions between two galaxies or when the merging of two black holes is disrupted. It has been estimated that there could be 12 rogue black holes in the Milky Way galaxy. OGLE-2011-BLG-0462/MOA-2011-BLG-191 In January 2022, a team of astronomers reported of OGLE-2011-BLG-0462 the first unambiguous detection and mass measurement of an isolated stellar black hole using the Hubble Space Telescope together with the Microlensing Observations in Astrophysics (MOA) and the Optical Gravitational Lensing Experiment (OGLE). This black hole is located 5,000 light-years away, has a mass 7.1 times that of the Sun, and moves at about 45 km/s. While there have been other candidates, they have been detected more indirectly. See also *Rogue planet *Black hole *Stellar black hole References ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optical Gravitational Lensing Experiment
The Optical Gravitational Lensing Experiment (OGLE) is a Polish astronomical project based at the University of Warsaw that runs a long-term variability sky survey (1992–present). The main goals are the detection and classification of variable stars ( pulsating and eclipsing), discovery of microlensing events, dwarf novae, and studies of the structure of the Galaxy and the Magellanic Clouds. Since the project began in 1992, it has discovered a multitude of extrasolar planets, together with the first planet discovered using the transit method (OGLE-TR-56b) and gravitational microlensing. The project has been led by professor Andrzej Udalski since its inception. Description The main targets of the experiment are the Magellanic Clouds and the Galactic Bulge, because of the large number of intervening stars that can be used for microlensing during a stellar transit. Most of the observations have been made at the Las Campanas Observatory in Chile. Cooperating institutions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
