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Tidal Disruption Event
A tidal disruption event (TDE) is a time-domain astronomy, transient astronomical source produced when a star passes so close to a supermassive black hole (SMBH) that it is pulled apart by the black hole's tidal force. The star undergoes spaghettification, producing a tidal stream (astrophysics), tidal stream of material that loops around the black hole. Some portion of the stellar material is captured into orbit, forming an accretion disk around the black hole, which emits electromagnetic radiation. In a small fraction of TDEs, a relativistic jet is also produced. As the material in the disk is gradually consumed by the black hole, the TDE fades over several months or years. TDEs were predicted in the 1970s and first observed in the 1990s. Over a hundred have since been observed, with detections at optical, infrared, radio and X-ray wavelengths. Sometimes a star can survive the encounter with an SMBH, leaving a remnant; those events are termed partial TDEs. History TDEs were f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EROSITA
eROSITA is an X-ray instrument built by the Max Planck Institute for Extraterrestrial Physics (MPE) in Germany. It is part of the Russian–German Spektr-RG space observatory, which also carries the Russian telescope ART-XC. It was launched by Roscosmos on 13 July 2019 from Baikonur, and deployed in a 6-month halo orbit around the second Lagrange point (L2). It began collecting data in October 2019. Due to the breakdown of institutional cooperation between Germany and Russia after the invasion of Ukraine, the instrument stopped collecting data on February 26, 2022. Overview eROSITA was originally designed by the ESA for the International Space Station, and it was concluded in 2005 that its accommodation on a dedicated free flyer would provide significantly improved scientific output. The eROSITA telescopes are based on the design of the ABRIXAS observatory launched in April 1999, whose battery was accidentally overcharged and destroyed three days after the mission star ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ASASSN-19bt
ASASSN-19bt was a tidal disruption event (TDE) known for being the first such event discovered. It was discovered by the All Sky Automated Survey for SuperNovae (ASAS-SN) project, with early-time, detailed observations by the TESS satellite. It was first detected on January 21, 2019, and reached peak brightness on March 4. The black hole which caused the TDE has a mass of around 6 million suns and is in the 16th magnitude galaxy 2MASX J07001137-6602251 in the constellation Volans at a redshift of 0.0262, around 375 million light years away. Observations in UV light made with NASA's Neil Gehrels Swift Observatory Neil Gehrels Swift Observatory, previously called the Swift Gamma-Ray Burst Explorer, is a NASA three-telescope space observatory for studying gamma-ray bursts (GRBs) and monitoring the afterglow in X-ray, and UV/visible light at the location o ... showed a drop in the temperature of the tidal disruption from around 71,500 to 35,500 degrees Fahrenheit (40,000 to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AT2018hyz
AT2018hyz is a tidal disruption event (TDE) that was discovered in 2018 by the All Sky Automated Survey for SuperNovae (ASASS-SN). History In 2022, astronomers announced the discovery of radio emission from AT2018hyz using the Very Large Array (VLA), MeerKAT, and the Australia Telescope Compact Array (ATCA), despite no radio emission detected earlier. The emission is still rising rapidly, and has been interpreted as an outflow of material that was "burped" several years after the initial TDE from the accretion disk of the supermassive black hole, traveling at up to half the speed of light. Alternately, it has been proposed that the delayed radio emission from AT2018hyz could be due to an off-axis astrophysical jet, which launched promptly when the black hole was consumed (similar to the TDE Swift J1644+57), and emission only became visible later when it entered our line of sight. Host galaxy The host galaxy for AT2018hyz is 2MASS J10065085+0141342, known as LEDA 3119592 or 2d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ASASSN-14li
ASASSN-14li was a tidal disruption event that occurred when a moderately massive star of 3 solar masses and significant CNO processing was tidally disrupted by a supermassive black hole in a galaxy around 290 million light years from Earth. However it could have been a low mass star that has been stripped of its envelope. If the star turns out to be around 3 solar masses, it would be one of the largest stars known to have experienced a tidal disruption event. The debris from the disrupted star showed relatively high amounts of nitrogen and carbon Carbon () is a chemical element; it has chemical symbol, symbol C and atomic number 6. It is nonmetallic and tetravalence, tetravalent—meaning that its atoms are able to form up to four covalent bonds due to its valence shell exhibiting 4 .... These elements were created during the tidal disruption event. References {{Reflist Tidal disruption events ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Swift J1644+57
Swift or SWIFT most commonly refers to: * SWIFT, an international organization facilitating transactions between banks ** SWIFT code * Swift (programming language) * Swift (bird), a family of birds It may also refer to: Organizations * SWIFT, an international organization facilitating transactions between banks * Swift Engineering, an American engineering firm * Swift & Company, a meat processing company * Swifts (aerobatic team), a Russian aerobatic team Transportation companies * Swift Cooper, a British racing car manufacturer * Swift Leisure, a British manufacturer of caravans * Swift Motor Company, of Coventry, England * Swift Transportation, a US trucking company Places * River Swift, a river in England * Swift, Illinois, an unincorporated community in northeastern Illinois * Swift County, Minnesota, a county in west-central Minnesota * Swift, Minnesota, an unincorporated community in northern Minnesota * Swift, Missouri, a ghost town in southeastern Missouri Astro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GRB 110328A (captured By The Hubble Space Telescope)
Swift J164449.3+573451, initially referred to as GRB 110328A, and sometimes abbreviated to Sw J1644+57, was a tidal disruption event (TDE), the destruction of a star by a supermassive black hole. It was first detected by the Swift Gamma-Ray Burst Mission on March 28, 2011. The event occurred in the center of a small galaxy in the Draco constellation, about 3.8 billion light-years away. It was the first confirmed jetted tidal disruption event and is the most luminous and energetic TDE recorded. Relativistic jet Swift J1644+57 occurred when a star wandered too close to the central supermassive black hole in the galaxy, and was gravitationally torn apart, forming an accretion disk from stellar material. When this occurred, an astrophysical jet was launched with material traveling at relativistic speeds, near the speed of light. The beam of radiation from one of these jets pointed directly toward Earth, enhancing the apparent brightness. Swift J1644+57 was observed by many tel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schwarzschild Radius
The Schwarzschild radius is a parameter in the Schwarzschild solution to Einstein's field equations that corresponds to the radius of a sphere in flat space that has the same surface area as that of the event horizon of a Schwarzschild black hole of a given mass. It is a characteristic quantity that may be associated with any quantity of mass. The Schwarzschild radius was named after the German astronomer Karl Schwarzschild, who calculated this solution for the theory of general relativity in 1916. The Schwarzschild radius is given as r_\text = \frac , where ''G'' is the Newtonian constant of gravitation, ''M'' is the mass of the object, and ''c'' is the speed of light. History In 1916, Karl Schwarzschild obtained an exact solution to the Einstein field equations for the gravitational field outside a non-rotating, spherically symmetric body with mass M (see ''Schwarzschild metric''). The solution contained terms of the form and , which have Mathematical singularity, singula ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roche Limit
In celestial mechanics, the Roche limit, also called Roche radius, is the distance from a celestial body within which a second celestial body, held together only by its own force of gravity, will disintegrate because the first body's tidal forces exceed the second body's self-gravitation. Inside the Roche limit, orbiting material disperses and forms rings, whereas outside the limit, material tends to coalesce. The Roche radius depends on the radius of the second body and on the ratio of the bodies' densities. The term is named after Édouard Roche (, ), the French astronomer who first calculated this theoretical limit in 1848. Explanation The Roche limit typically applies to a satellite's disintegrating due to tidal forces induced by its ''primary'', the body around which it orbits. Parts of the satellite that are closer to the primary are attracted more strongly by gravity from the primary than parts that are farther away; this disparity effectively pulls the near an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astrophysical Jet
An astrophysical jet is an astronomical phenomenon where outflows of ionised matter are emitted as extended beams along the axis of rotation. When this greatly accelerated matter in the beam approaches the speed of light, astrophysical jets become relativistic jets as they show effects from special relativity. The formation and powering of astrophysical jets are highly complex phenomena that are associated with many types of high-energy astronomical sources. They likely arise from dynamic interactions within accretion disks, whose active processes are commonly connected with compact central objects such as black holes, neutron stars or pulsars. One explanation is that tangled magnetic fields are organised to aim two diametrically opposing beams away from the central source by angles only several degrees wide Jets may also be influenced by a general relativity effect known as frame-dragging. Most of the largest and most active jets are created by supermassive black holes (SM ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Type Ib And Ic Supernovae
Type Ib and Type Ic supernovae are categories of supernovae that are caused by the stellar core collapse of massive stars. These stars have shed or been stripped of their outer envelope of hydrogen, and, when compared to the spectrum of Type Ia supernovae, they lack the absorption line of silicon. Compared to Type Ib, Type Ic supernovae are hypothesized to have lost more of their initial envelope, including most of their helium. Spectra When a supernova is observed, it can be categorized in the Minkowski– Zwicky supernova classification scheme based upon the absorption lines that appear in its spectrum. A supernova is first categorized as either a Type I or Type II, then subcategorized based on more specific traits. Supernovae belonging to the general category Type I lack hydrogen lines in their spectra; in contrast to Type II supernovae which do display lines of hydrogen. The Type I category is subdivided into Type Ia, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supernovae
A supernova (: supernovae or supernovas) is a powerful and luminous explosion of a star. A supernova occurs during the last evolutionary stages of a massive star, or when a white dwarf is triggered into runaway nuclear fusion. The original object, called the ''progenitor'', either collapses to a neutron star or black hole, or is completely destroyed to form a diffuse nebula. The peak optical luminosity of a supernova can be comparable to that of an entire galaxy before fading over several weeks or months. The last supernova directly observed in the Milky Way was Kepler's Supernova in 1604, appearing not long after Tycho's Supernova in 1572, both of which were visible to the naked eye. The remnants of more recent supernovae have been found, and observations of supernovae in other galaxies suggest they occur in the Milky Way on average about three times every century. A supernova in the Milky Way would almost certainly be observable through modern astronomical telescopes. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
