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27-486: NAOC may refer to: National Astronomical Observatories, Chinese Academy of Sciences (中国科学院国家天文台) Nagano Olympic Organizing Committee of the 1998 Winter Olympic Games National Airborne Operations Center , the Boeing E-4B aircraft The New Adventures of Old Christine , an American comedy series starring Julia Louis-Dreyfus New American Opportunity Campaign ,

54-669: A NASA probe, itself in orbit around the Sun , was saturated by the blast of radiation. It soon hit Venus, where the Pioneer Venus Orbiter 's detectors were overcome by the wave. Shortly thereafter the gamma rays inundated the detectors of three U.S. Department of Defense Vela satellites , the Soviet Prognoz 7 satellite , and the Einstein Observatory , all orbiting Earth. Before exiting the solar system

81-576: A biannual orienteering competition hosted by Canada and the United States Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title NAOC . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=NAOC&oldid=1242353670 " Category : Disambiguation pages Hidden categories: Short description

108-652: A campaign of the Coalition for Comprehensive Immigration Reform Netherlands Antilles Olympic Committee , the National Olympic Committee of Curaçao, Sint Maarten, Bonaire, Sint Eustatius and Saba Nigerian Agip Oil Company , Nigerian company owned by Oando PLC North Absheron Operating Company , oil consortium established in Azerbaijan for development of Dan Ulduzu and Ashrafi oil and gas fields North American Orienteering Championships ,

135-705: A dynamic range over 30 magnitudes, plotted a clear structure of dark matter haloes with mass ranging from earth-size to cosmological scale. The simulation provides a detailed universe structure under L-CDM model. NAOC took part in a wide range of International collaborations, include Square Kilometre Array (SKA), Thirty Meter Telescope (TMT), Herschel Space Observatory , and Beijing-Arizona Sky Survey (BASS), etc. Meanwhile, several NAOC developing projects are also international collaborated, including FAST. NAOC also started cooperation with futuristic projects like Einstein Probe (EP), CSST, etc. Magnetar A magnetar

162-446: A few months after the successful dropping of landers into the atmosphere of Venus , the two uncrewed Soviet spaceprobes Venera 11 and 12 , then in heliocentric orbit , were hit by a blast of gamma radiation at approximately 10:51 EST. This contact raised the radiation readings on both the probes from a normal 100 counts per second to over 200,000 counts a second in only a fraction of a millisecond. Eleven seconds later, Helios 2 ,

189-501: A hundred million times stronger than any man-made magnet, and about a trillion times more powerful than the field surrounding Earth . Earth has a geomagnetic field of 30–60 microteslas, and a neodymium-based, rare-earth magnet has a field of about 1.25 tesla, with a magnetic energy density of 4.0 × 10 J/m . A magnetar's 10 tesla field, by contrast, has an energy density of 4.0 × 10  J/m , with an E / c mass density more than 10,000 times that of lead . The magnetic field of

216-477: A magnetar close to supernova remnant Kesteven 79 . Astronomers from Europe and China discovered this magnetar, named 3XMM J185246.6+003317, in 2013 by looking at images that had been taken in 2008 and 2009. In 2013, a magnetar PSR J1745−2900 was discovered, which orbits the black hole in the Sagittarius A* system. This object provides a valuable tool for studying the ionized interstellar medium toward

243-717: A magnetar is short compared to other celestial bodies. Their strong magnetic fields decay after about 10,000 years, after which activity and strong X-ray emission cease. Given the number of magnetars observable today, one estimate puts the number of inactive magnetars in the Milky Way at 30 million or more. Starquakes triggered on the surface of the magnetar disturb the magnetic field which encompasses it, often leading to extremely powerful gamma-ray flare emissions which have been recorded on Earth in 1979, 1998 and 2004. Magnetars are characterized by their extremely powerful magnetic fields of ~10 to 10 T . These magnetic fields are

270-575: A magnetar would be lethal even at a distance of 1,000 km due to the strong magnetic field distorting the electron clouds of the subject's constituent atoms, rendering the chemistry of sustaining life impossible. At a distance of halfway from Earth to the moon, an average distance between the Earth and the Moon being 384,400 km (238,900 miles), a magnetar could wipe information from the magnetic stripes of all credit cards on Earth. As of 2020 , they are

297-421: A magnetar. This suggests that magnetars are not merely a rare type of pulsar but may be a (possibly reversible) phase in the lives of some pulsars. On September 24, 2008, ESO announced what it ascertained was the first optically active magnetar-candidate yet discovered, using ESO's Very Large Telescope . The newly discovered object was designated SWIFT J195509+261406. On September 1, 2014, ESA released news of

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324-671: A mass of about 1.4 solar masses. They are formed by the collapse of a star with a mass 10–25 times that of the Sun . The density of the interior of a magnetar is such that a tablespoon of its substance would have a mass of over 100 million tons. Magnetars are differentiated from other neutron stars by having even stronger magnetic fields, and by rotating more slowly in comparison. Most observed magnetars rotate once every two to ten seconds, whereas typical neutron stars, observed as radio pulsars , rotate one to ten times per second. A magnetar's magnetic field gives rise to very strong and characteristic bursts of X-rays and gamma rays. The active life of

351-450: A newly formed neutron star falls into the right ranges, a dynamo mechanism could act, converting heat and rotational energy into magnetic energy and increasing the magnetic field, normally an already enormous 10 teslas , to more than 10 teslas (or 10 gauss ). The result is a magnetar . It is estimated that about one in ten supernova explosions results in a magnetar rather than a more standard neutron star or pulsar. On March 5, 1979,

378-473: Is a type of neutron star with an extremely powerful magnetic field (~10 to 10 T , ~10 to 10 G ). The magnetic-field decay powers the emission of high- energy electromagnetic radiation , particularly X-rays and gamma rays . The existence of magnetars was proposed in 1992 by Robert Duncan and Christopher Thompson . Their proposal sought to explain the properties of transient sources of gamma rays, now known as soft gamma repeaters (SGRs). Over

405-481: Is different from Wikidata All article disambiguation pages All disambiguation pages National Astronomical Observatory of China Founded on April 25, 2001, NAOC was formed through the merging of four Chinese Academy of Sciences (CAS) observatories, three CAS observing stations and one CAS research centre. The Headquarters of the NAOC are situated in the northern Chaoyang District of Beijing on

432-512: Is given in the McGill SGR/AXP Online Catalog. Examples of known magnetars include: Unusually bright supernovae are thought to result from the death of very large stars as pair-instability supernovae (or pulsational pair-instability supernovae). However, recent research by astronomers has postulated that energy released from newly formed magnetars into the surrounding supernova remnants may be responsible for some of

459-408: Is that they simply result from the collapse of stars with unusually strong magnetic fields. In a supernova , a star collapses to a neutron star, and its magnetic field increases dramatically in strength through conservation of magnetic flux . Halving a linear dimension increases the magnetic field strength fourfold. Duncan and Thompson calculated that when the spin, temperature and magnetic field of

486-704: The Five-hundred-meter Aperture Spherical radio Telescope (FAST). The future China Space Station Telescope (CSST) will also be operated by NAOC. Editorial departments of Research in Astronomy and Astrophysics (RAA) and China National Astronomy (中国国家天文) are located in NAOC. NAOC currently have 4 direct subordinate units, with 2 astronomical observatory, 1 artificial satellite observing station and 1 astronomical instrument developing institute. In 2019, FAST observation to fast radio burst (FRB) event FRB180301 reveals that

513-553: The Galactic Center . In 2018, the temporary result of the merger of two neutron stars was determined to be a hypermassive magnetar, which shortly collapsed into a black hole. In April 2020, a possible link between fast radio bursts (FRBs) and magnetars was suggested, based on observations of SGR 1935+2154 , a likely magnetar located in the Milky Way galaxy. As of July 2021 , 24 magnetars are known, with six more candidates awaiting confirmation. A full listing

540-619: The following decade, the magnetar hypothesis became widely accepted, and was extended to explain anomalous X-ray pulsars (AXPs). As of July 2021 , 24 magnetars have been confirmed. It has been suggested that magnetars are the source of fast radio bursts (FRB), in particular as a result of findings in 2020 by scientists using the Australian Square Kilometre Array Pathfinder (ASKAP) radio telescope. Like other neutron stars , magnetars are around 20 kilometres (12 mi) in diameter, and have

567-468: The most powerful magnetic objects detected throughout the universe. As described in the February 2003 Scientific American cover story, remarkable things happen within a magnetic field of magnetar strength. " X-ray photons readily split in two or merge. The vacuum itself is polarized , becoming strongly birefringent , like a calcite crystal. Atoms are deformed into long cylinders thinner than

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594-413: The neutron star settles into its equilibrium configuration. These fields then persist due to persistent currents in a proton-superconductor phase of matter that exists at an intermediate depth within the neutron star (where neutrons predominate by mass). A similar magnetohydrodynamic dynamo process produces even more intense transient fields during coalescence of pairs of neutron stars. An alternative model

621-451: The origin of FRBs should be inside the magnetosphere of designated object. In 2020, another FRB event FRB200428, which was later confirmed to be originated from magnetar SGR J1935+2154, was observed in detail by FAST team. Research suggests that a low correlation between FRBs and magnetar X-ray burst. In 2020, NAOC and its collaborators performed a numerical simulation to dark matter halo between galaxies. This GADGET-4 simulation, with

648-413: The quantum-relativistic de Broglie wavelength of an electron." In a field of about 10 teslas atomic orbitals deform into rod shapes. At 10 teslas, a hydrogen atom becomes 200 times as narrow as its normal diameter. The dominant model of the strong fields of magnetars is that it results from a magnetohydrodynamic dynamo process in the turbulent, extremely dense conducting fluid that exists before

675-506: The radiation was detected by the International Sun–Earth Explorer in halo orbit . This was the strongest wave of extra-solar gamma rays ever detected at over 100 times as intense as any previously known burst. Given the speed of light and its detection by several widely dispersed spacecraft, the source of the gamma radiation could be triangulated to within an accuracy of approximately 2 arcseconds . The direction of

702-532: The site of the former Beijing Astronomical Observatory (BAO), and take responsibility for all matters relating to the former BAO. Currently, NAOC has 7 astronomical research departments listed follows: Besides apparatus like 2.16m optical telescope and 50m radio telescope, NAOC also operates the Large Sky Area Multi-Object Fiber Spectroscopy Telescope (LAMOST) and one of the largest radio observatory,

729-535: The source corresponded with the remnants of a star that had gone supernova around 3000 BCE . It was in the Large Magellanic Cloud and the source was named SGR 0525-66 ; the event itself was named GRB 790305b , the first-observed SGR megaflare. On February 21, 2008, it was announced that NASA and researchers at McGill University had discovered a neutron star with the properties of a radio pulsar which emitted some magnetically powered bursts, like

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