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MOA-2007-BLG-192L
MOA-2007-BLG-192L is a low-mass red dwarf star or brown dwarf, approximately 3,000 light-years away in the constellation of Sagittarius. It is estimated to have a mass approximately 6% of the Sun's. In 2008, an Earth-sized extrasolar planet was announced to be orbiting this object. Planetary system The discovery of a planet, MOA-2007-BLG-192Lb, orbiting this object was announced on June 2, 2008. MOA-2007-BLG-192Lb: A Low-Mass Planet with a Possible Sub-Stellar-Mass Host , David P. Bennett. Accessed on line July 3, 2008. This planet, with a mass of approximately 3.3 times that of , is one of the smallest known extrasolar |
MOA-2007-BLG-192Lb
MOA-2007-BLG-192Lb, occasionally shortened to MOA-192 b, , JPL. Accessed on line July 2, 2008. is an approximately 3,000 light-years away in the constellation of Sagittarius. The planet was discovered orbiting the |
Brown Dwarf
Brown dwarfs (also called failed stars) are substellar objects that are not massive enough to sustain nuclear fusion of ordinary hydrogen ( 1H) into helium in their cores, unlike a main-sequence star. Instead, they have a mass between the most massive gas giant planets and the least massive stars, approximately 13 to 80 times that of Jupiter (). However, they can fuse deuterium ( 2H), and the most massive ones (> ) can fuse lithium ( 7Li). Astronomers classify self-luminous objects by spectral class, a distinction intimately tied to the surface temperature, and brown dwarfs occupy types M, L, T, and Y. As brown dwarfs do not undergo stable hydrogen fusion, they cool down over time, progressively passing through later spectral types as they age. Despite their name, to the naked eye, brown dwarfs would appear in different colors depending on their temperature. The warmest ones are possibly orange or red, while cooler brown dwarfs would likely appear magenta or black to th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mount John University Observatory
University of Canterbury Mount John Observatory (UCMJO), previously known as Mt John University Observatory (MJUO), is New Zealand's premier astronomical research observatory. It is situated at ASL atop Mount John at the northern end of the Mackenzie Basin in the South Island, and was established in 1965. There are many telescopes on site including: one 0.4-meter, two 0.6-meter, one 1.0-meter, and a new 1.8-meter MOA Telescope. The nearest population center is the resort town Lake Tekapo (pop. <500). Approximately 20% of nights at MJUO are photometric, with a larger number available for spectroscopic work and direct imaging photometry. UCMJO is operated by the University of Canterbury, and is the home of HERCULES (High Efficiency and Resolution Canterbury University Large Echelle Spectrograph), and the observational wing of the Japanese/New Zealand MOA collaboration (Microlensing Observations in Astrophysics) led by Professor Yasushi Muraki of Nagoya University. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gravitational Microlensing
Gravitational microlensing is an astronomical phenomenon due to the gravitational lens effect. It can be used to detect objects that range from the mass of a planet to the mass of a star, regardless of the light they emit. Typically, astronomers can only detect bright objects that emit much light (stars) or large objects that block background light (clouds of gas and dust). These objects make up only a minor portion of the mass of a galaxy. Microlensing allows the study of objects that emit little or no light. When a distant star or quasar gets sufficiently aligned with a massive compact foreground object, the bending of light due to its gravitational field, as discussed by Albert Einstein in 1915, leads to two distorted images (generally unresolved), resulting in an observable magnification. The time-scale of the transient brightening depends on the mass of the foreground object as well as on the relative proper motion between the background 'source' and the foreground 'lens' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microlensing
Gravitational microlensing is an astronomical phenomenon due to the gravitational lens effect. It can be used to detect objects that range from the mass of a planet to the mass of a star, regardless of the light they emit. Typically, astronomers can only detect bright objects that emit much light (stars) or large objects that block background light (clouds of gas and dust). These objects make up only a minor portion of the mass of a galaxy. Microlensing allows the study of objects that emit little or no light. When a distant star or quasar gets sufficiently aligned with a massive compact foreground object, the bending of light due to its gravitational field, as discussed by Albert Einstein in 1915, leads to two distorted images (generally unresolved), resulting in an observable magnification. The time-scale of the transient brightening depends on the mass of the foreground object as well as on the relative proper motion between the background 'source' and the foreground 'lens' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MOA-2007-BLG-400L
MOA-2007-BLG-400L is a star located approximately 20000 light-years away in the constellation of Sagittarius. This star is presumed to be a red dwarf with a spectral type of M3V, based on its mass of 0.35 MS. Planetary system In September 2008, the discovery of an extrasolar planet was announced by the Microlensing Follow Up Network (μFUN) and the Microlensing Observations in Astrophysics (MOA) Collaboration. This planet was detected by the gravitational microlensing method based on an event recorded in September 2007. See also * List of extrasolar planets * MOA-2007-BLG-192L MOA-2007-BLG-192L is a low-mass red dwarf star or brown dwarf, approximately 3,000 light-years away in the constellation of Sagittarius. It is estimated to have a mass approximately 6% of the Sun's. In 2008, an Earth-sized extrasolar plane ... References web preprint External links MOA-2007-BLG-400 Event M-type main-sequence stars Planetary systems with one confirmed planet Sa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HD 47186
HD 47186 is a star located approximately 129 light-years away in the constellation of Canis Major. It is a G6V star with the characteristics very similar to the Sun, but it is 1.7 times more metal-rich. In 2008, two extrasolar planets were discovered orbiting the star. Planetary system Announced in June 2008, two extrasolar planets were discovered orbiting the star. Both planets are less massive than Jupiter. The inner planet HD 47186 b orbits close to the star and is termed a “hot Neptune”. The outer planet HD 47186 c orbits in a similar distance from the star as the asteroid Vesta, at around 2.4 AU. The inner planet orbits in a circular path while the outer planet orbits in an eccentric path. See also * HD 181433 * HD 40307 * MOA-2007-BLG-192L MOA-2007-BLG-192L is a low-mass red dwarf star or brown dwarf, approximately 3,000 light-years away in the constellation of Sagittarius. It is estimated to have a mass approximately 6% of the Sun's. In 200 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HD 40307
HD 40307 is an orange ( K-type) main-sequence star located approximately 42 light-years away in the constellation of Pictor (the Easel), taking its primary name from its Henry Draper Catalogue designation. It is calculated to be slightly less massive than the Sun. The star has six known planets, three discovered in 2008 and three more in 2012. One of them, HD 40307 g, is a potential super-Earth in the habitable zone, with an orbital period of about 200 days. This object might be capable of supporting liquid water on its surface, although much more information must be acquired before its habitability can be assessed. No stellar companions to HD 40307 were detected as in 2018. History and nomenclature HD 40307 was observed during or before 1900 as part of the Cape Photographic Durchmusterung. The designation ''HD 40307'' is from the Henry Draper Catalogue, which is based on spectral classifications made between 1911 and 1915 by Annie Jump Cannon and her co-workers, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HD 181433
HD 181433 is a star located approximately 87 light-years away in the constellation of Pavo (the Peacock). According to SIMBAD, it has a stellar classification of K3III-IV, which puts it on the borderline between being a red giant and a subgiant. This is inconsistent with the fact that its luminosity is only 0.308 times that of the Sun. Its entry in the Hipparcos catalogue lists a spectral type of K5V, classifying it as a dwarf star. , three extrasolar planets are thought to be orbiting the star. There is currently little information on these planets. The name of this star comes from its identifier in the Henry Draper catalogue. Planetary system Orbiting the star are three planets, whose discovery was announced in 2008; the discovery paper was published in 2009. The inner planet has a mass at least 7.5 times that of Earth, and is termed a super-Earth (this classification is based solely on the mass of the planet and should not be taken to imply that the planet could su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 Experime ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OGLE-2005-BLG-390L
OGLE-2005-BLG-390L is a star thought to be a spectral type M (a red dwarf; 95% probability, 4% probability it is a white dwarf, <1% probability it is a or ). This dim 16 is located in the |
New Zealand
New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island country by area, covering . New Zealand is about east of Australia across the Tasman Sea and south of the islands of New Caledonia, Fiji, and Tonga. The country's varied topography and sharp mountain peaks, including the Southern Alps, owe much to tectonic uplift and volcanic eruptions. New Zealand's capital city is Wellington, and its most populous city is Auckland. The islands of New Zealand were the last large habitable land to be settled by humans. Between about 1280 and 1350, Polynesians began to settle in the islands and then developed a distinctive Māori culture. In 1642, the Dutch explorer Abel Tasman became the first European to sight and record New Zealand. In 1840, representatives of the United Kingdom and Māori chiefs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
