Автор che wi, 05.11.2016 13:28:35
0 Пользователей и 1 гость просматривают эту тему.
ЦитатаМежду тем, в ближайшие месяцы до конца 2016 года китайские ученые планируют осуществить запуск модуляционного телескопа жесткого рентгеновского диапазона HXMT (Hard X-ray Modulation Telescope).Предполагается, что данный аппарат произведет обзор небесной сферы в жестких рентгеновских лучах и, возможно, обнаружит примерно 1000 новых источников, включая активные галактические ядра, квазары и объекты галактического фона, а затем будет выполнять детальное исследование отдельных объектов, в числе которых черные дыры и нейтронные звезды.HXMT также будет осуществлять мониторинг иных интересных космических источников и проводить периодический обзор галактической плоскости.Впервые проект HXMT был предложен китайскими учеными еще в 1994 году. В апреле 2000 года он вошел в список основных государственных проектов в области фундаментальных исследований («проект 973»). В 2004 году был изготовлен наземный прототип HXMT и выполнены испытания прибора на аэростатах. Финансирование работ проводят Министерство науки и техники, Китайская академия наук и Университет Цинхуа.
ЦитатаThe Hard X-ray Modulation Telescope (HXMT) is China's first astronomical satellite. There are three main payloads onboard HXMT, the high energy X-ray telescope (20-250 keV, 5100 cm2), the medium energy X-ray telescope (5-30 keV, 952 cm2), and the low energy X-ray telescope (1-15 keV, 384 cm2). The main scientific objectives of HXMT are: (1) to scan the Galactic Plane to find new transient sources and to monitor the known variable sources, and (2) to observe X-ray binaries to study the dynamics and emission mechanism in strong gravitational or magnetic fields.
Цитатаche wi пишет: Цитата... модуляционного телескопа жесткого рентгеновского диапазона HXMT (Hard X-ray Modulation Telescope).
Цитата... модуляционного телескопа жесткого рентгеновского диапазона HXMT (Hard X-ray Modulation Telescope).
ЦитатаHXMT to launch in June with two Zhuhai-1 video microsatellites for the Orbita system.Launch vehicle is a CZ-4B.
Цитата ChinaSpaceflight @cnspaceflight 9 ч. назад【珠海一号】欧比特称两颗视频试验卫星预计搭载硬X射线调制望远镜主卫星发射任务，由长征四号B型火箭执行发射任务。https://goo.gl/I8qsi8
Цитата[Zhuhai One] OBB said two video test satellites are expected to carry hard X-ray telescope main satellite launch mission, by the Long March IV B rocket execution mission.
ЦитатаOu Bite: The company's two video test satellites are expected to carry a hard X-ray telescope main satellite launch mission, carried out by the Long March IV B rocket launch mission. The company has been to communicate with the launch unit, for the middle of June in Jiuquan launch site to complete the first two video test satellite carrying launch mission.
ЦитатаПекин, 29 мая /Синьхуа/ -- Китай планирует запустить новую космическую обсерваторию для исследования многих загадок Вселенной, включая активные ядра галактик на краю Вселенной.Ученые обнаружили, что в центре почти всех галактик имеется сверхмассивная черная дыра, масса которой в миллионы и даже миллиарды раз превышает массу Солнца. Согласно закону всемирного тяготения сверхмассивная черная дыра активно поглощает близлежащие пыль и газ.Когда черная дыра поглощает слишком много, избыточное вещество превращается в две релятивистские струи, перпендикулярные аккреционному диску черной дыры.Релятивистские струи и аккреционный диск сверхмассивной черной дыры генерируют мощное рентгеновское излучение, которое способно преодолеть расстояние в несколько миллиардов световых лет. Эти галактики имеют очень яркие ядра, настолько яркие, что центральная область может быть более освещенной, чем вся остальная часть галактики. Такие ядра называют активными ядрами галактик.Разработанный китайскими учеными телескоп для работы с жестким рентгеновским излучением /Hard X-ray Modulation Telescope, HXMT/ предназначен для наблюдения за некоторыми активными ядрами галактик."Активные ядра галактик находятся очень далеко от Земли, поэтому наш телескоп может зондировать только самые яркие из них", - рассказал научный руководитель проекта HXMT, заведующий ключевой лабораторией физики элементарных частиц и астрономии Академии наук Китая Чжан Шуаннань.Ученые пока не знают, как сверхмассивные черные дыры образуются и развиваются, что является ключом к пониманию эволюции галактик.Ожидается, что HXMT поможет ученым наблюдать за ядерным диапазоном, находящимся близко от горизонта событий сверхмассивных черных дыр в центре активных галактик, и собрать информацию о чрезвычайно сильных гравитационных полях, сообщил Чжан Шуаннань.
ЦитатаSINCE the detection of gravitational waves, scientists have been eager to find corresponding electromagnetic signals. This will be an important task for China's space telescope, the Hard X-ray Modulation Telescope, due to launch this year. Скрытый текст: Gravitational waves are "ripples" in the fabric of spacetime caused by some of the most violent and energetic processes in the universe. Einstein predicted the existence of gravitational waves in 1916 in his general theory of relativity.He showed that massive accelerating objects, such as neutron stars or black holes orbiting each other, would disrupt spacetime in such a way that "waves" of distorted space would radiate from the source, like ripples from a stone thrown into a pond.These ripples would travel at the speed of light through the universe, carrying with them information about their origin, as well as clues to the nature of gravity itself.The strongest gravitational waves are produced by events such as colliding black holes, supernova explosions, coalescing neutron stars or white dwarf stars, the slightly wobbly rotation of neutron stars that are not perfect spheres, and the remnants of gravitational radiation created by the birth of the universe itself.On February 11 last year, the Laser Interferometer Gravitational-Wave Observatory in the United States announced the first observation of gravitational waves. On June 15 the same year, the second detection of a gravitational wave event from colliding black holes was announced.Increased reliabilityXiong Shaolin, a scientist at the Institute of High Energy Physics of the Chinese Academy of Sciences, says the position accuracy of all the gravitational wave events detected so far is still poor.If scientists can find electromagnetic signals happening at similar positions and times of the gravitational wave events, it will increase the reliability of the detection, he said. Combined analysis of the gravitational wave and electromagnetic signals will help reveal more about the celestial bodies emitting the waves.Scientists have yet to detect electromagnetic signals corresponding to gravitational waves. Many scientists would regard detecting gravitational waves and corresponding electromagnetic signals as a major scientific discovery. Some suspect that mysterious gamma-ray bursts could be electromagnetic signals corresponding to gravitational waves.Brightest eventsGamma-ray bursts are extremely energetic explosions that have been observed in distant galaxies. They are the brightest electromagnetic events known to occur in the universe. Bursts can last from several milliseconds to more than an hour.The intense radiation of most observed gamma-ray bursts is believed to be released by a supernova as a rapidly rotating, high-mass star collapses to form a neutron star or black hole. A subclass of bursts appears to originate from a different process: the merger of binary neutron stars, or the merger of a neutron star and a black hole.About 0.4 seconds after the first gravitational event was detected on September 14, 2015, NASA's Fermi Gamma-Ray Space Telescope detected a relatively weak gamma-ray burst, which lasted about a second.But scientists disagree on whether these two events are related, and no other gamma-ray burst probe detected a gamma-ray burst. Scientists need more evidence to clarify the relationship between gamma-ray bursts and gravitational waves.Zhang Shuangnan, lead scientist of HXMT and director of the Key Laboratory of Particle Astrophysics of CAS, said: "Since gravitational waves were detected, the study of gamma-ray bursts has become more important. In astrophysics research, it's insufficient to study just the gravitational wave signals. We need to use the corresponding electromagnetic signals, which are more familiar to astronomers, to facilitate the research on gravitational waves."HXMT's effective detection area for monitoring gamma-ray bursts is 10 times that of the Fermi space telescope. "HXMT can play a vital role in searching for electromagnetic signals corresponding to gravitational waves," says Zhang."If HXMT can detect the electromagnetic signals corresponding to gravitational waves, it would be its most wonderful scientific finding."
ЦитатаHXMT - Hard X-Ray Modulation TelescopeImage: Xinhua/SASTINDThe Hard X-Ray Modulation Telescope (HXMT) is a Chinese X-Ray Space Observatory launching in 2017 as the country's prime X-ray astronomy mission to observe black holes, neutron stars and other intense X-ray and gamma-ray sources to study the high-energy universe.A project of several institutes in China, HXMT hosts three collimated X-ray telescopes tasked with a full scan of the Galactic Plane to find new transient X-ray sources, monitor known sources, and to observer X-ray binaries to study dynamic phenomena in intense gravitational and magnetic fields. Скрытый текст: The 2.8-metric-ton observatory has had an extraordinarily long road to launch, first proposed in 1993 and sel ected for further study in 2000 to advance to the development stage with an initial plan of launching in 2010. However, these plans could not be realized and HXMT ended up requiring funding under three of China's Five-Year Plans as the project evolved through the addition of payloads and optimization for the working conditions found in Low Earth OrbitPhoto: IHEPThe mission's design was eventually frozen in 2011 when approval was given for the project to enter into hardware manufacture, starting with the fully functional ground testbed before the flight unit began assembly after 2012.Part of the HXMT Project are the Chinese Ministry of Science and Technology, the Chinese Academy of Sciences, Tsinghua University and satellite platform builder CAST. According to the HXMT Project, the Institute of High Energy Physics at CAS and Tsinghua University were responsible for the development of the Payload Module while CAST designed the satellite platform - reportedly based on heritage fr om the Ziyuan-2 Earth Observation Satellites which were based on high-resolution military imaging satellites and used the Phoenix-Eye-2 satellite bus.The Ziyuan-2 satellites were among the largest and heaviest Chinese satellites when being launched between 2000 and 2004, hosting medium-resolution imaging payloads to capture Earth imagery at a 3-meter ground resolution. Ziyuan-2 entered development in 1993, the same year HXMT was first proposed, providing a connection between the platform and mission.Image: CASTPhoenix Eye-2, optimized for operation in Low Earth Orbit, can have launch masses in excess of 2,600 Kilograms featuring two three-panel solar arrays, a three-axis attitude determination and control platform for precise pointing, and a propulsion system consisting of orbit correction engines and attitude control thrusters.The HXMT satellite measures 2.0 by 2.0 by 2.8 meters in size and has a launch mass of 2,800 Kilograms with the payload making up more than one metric ton of the satellite's initial mass. According to the project, HXMT provides excellent three-axis stabilization with a control precision of +/-0.1 degrees, pointing knowledge better than 0.01° and attitude stability of 0.005°/sec. The payload module is 1.9 by 1.65 by 1.0 meters in size.HXMT carries three main payloads, all slat-collimated X-ray telescopes that cover different energy ranges to create a system that can deliver high-resolution images and spectral data over a broad energy range.HXMT Payload Section - Image: CAS/HXMT ProjectThe biggest of the three is the high-energy X-ray telescope (HE) that covers an energy range of 20 to 250 kilo-electronvolt and has a large active area of 5,100cm². ME, the medium-energy X-ray telescope, covers energies of 5 to 30 keV with an active area of 952cm2, and the 384cm² low-energy X-ray telescope (LE) is sensitive for X-rays between 1 and 15keV. Additionally, HXMT hosts a CsI detector to detect gamma-ray bursts.The typical field of view of HXMT's aligned telescopes is 1° x 6° with additional fields of view toward other directions in order to obtain measurements of the cosmic X-ray background.HXMT will be tasked with two different types of measurements - an all-sky survey around the Galactic Plane and focused observations on objects of interest to obtain their broad band spectra and multi-wavelength temporal properties. The sky survey is intended to discover new X-ray sources including transient objects that are of particular interest for further scrutiny.Image: HXMT ProjectSpecifically, HXMT aims to conduct measurements on various types of Active Galactic Nuclei (AGNs, supermassive black holes) to help understand the nature of the cosmic X-ray background.The mission will also study the quasi-periodic oscillation and other time-constrained phenomena of black holes and neutron star X-ray binaries, taking advantage of the telescope's large active area that allows for the study of short time-scale variability. Observations will also me made to examine the cyclotron resonance features and the magnetic field strength of ultra-dense neutron stars and remnants of supernova explosions will be studied for their non-thermal X-ray emission properties and mechanisms of particle acceleration.HXMT stands out among other X-ray missions for its combination of high-angular resolution, time resolution and spectral resolution as well as its multi-use capability for all-sky scans and narrow-field pointed observations. Its method of direct demodulation to reconstruct X-ray images at high angular resolution is also a novelty in space-based X-ray astronomy.Image: HXMT ProjectOne unique aspect of the HXMT mission is the ability to rapidly target transient sources. As part of its scan of the Galactic Plane, the telescope is expected to detect a number of new transient sources as well as X-Ray binaries in their high-emission state.A quick-look software algorithm will analyze scanning data collected every day and identify the position and flux of transient sources. When a source of interest is found, pointed observations can be put into the spacecraft's operational plan within 24 hours of the first detection to capture valuable data.The High-Energy X-Ray Telescope (HE) comprises 18 NaI/CsI phoswich detectors arranged in the central section of the Payload Module using two concentric circles with six elements in the inner circle and 12 elements in the outer circle.Image: HXMT ProjectPhoswich elements, short for phosphor sandwich, employ a combination of different scintillating materials which absorb the energy of an incoming X-ray or gamma-ray photon and re-emit the energy in the form of light which can be measured using conventional photo-detectors. In a phoswich, two scintillators with different pulse shape characteristics are optically coupled and interface with a photo-multiplier. Analysis of the pulse shape is used to distinguish signals fr om the two scintillators to identify the scintillator in which the event occurred.The advantage of phoswich detectors comes in the measurement of low-energy gamma- and X-rays as well as measurements in a higher-background environment.In HXMT's case, the scintillators are Sodium Iodide doped with Thallium and Caesium Iodide doped with Sodium. Each phoswich crystal element is 19 centimeters in diameter, the 3.5mm thick NaI crystal lies directly behind a Beryllium window and the 40mm CsI crystal is located underneath the NaI. The full energy of an incident X-ray is deposited into the NaI crystal while the CsI is used as active shielding to reject events fr om the back side.HE Detector Element - Image: HXMT ProjectImage: HXMT ProjectEach of the 18 HE detector elements have an active area of 283.5cm² and in front of the detectors themselves reside Tantalum & Tungsten collimators that set the field of view for each detector.Fifteen of the detectors have a field of view of 1.14 by 5.71 degrees, two have a larger 5.71 by 5.71-degree FOV for background detection and the final element is fully blocked with a 2mm tantalum shield for dark current measurements. The overall active instrument FOV is 5.71 by 5.71 degrees. Surrounding the detector assemblies on all sides except the optical axis are scintillating plastic plates that act as veto to depress events caused by particles not arriving on the instrument's optical axis.Underneath the phoswich stack is a quartz separator that couples the scintillator to the Photomultiplier tube in which the visible radiation photons are converted into electrons which can produce an electrical signal that can me measured. Photomultipliers make use of the photoelectric effect, creating free electrons when photons strike the photocathode element. The electrons are directed through an electron multiplier that comprises a series of dynodes wh ere secondary emission takes place to create sufficient electrons to produce a measurable current.[HXMT Instrument Package - Image: HXMT ProjectHE is capable of simultaneous spectral measurements, timing and imaging. Also, the instrument is capable of doubling as a gamma-ray detector, sensitive in an energy range of 40 to 600 keV in normal operations mode and 200 keV to 2 MeV when in GRB mode. In this mode, the instrument will be important for observations of Gamma-ray burst spectra and the search for the electro-magnetic counterpart to gravitational waves which have only recently been proven to be a real concept.Each of the 18 high-energy X-ray telescopes has its own high-gain controller, installed in the corresponding collimator grid and adjusting the photo-detector voltage in real time to keep a stable detector gain.Three particle monitors installed on the instrument deck are in charge of measuring the influx of high-energy protons and electrons. If charged particle flux is higher than a programmed threshold, the high voltages of the detectors will be automatically decreased to avoid damaging the photomultiplier tubes. An additional requirement for HE is a stable thermal environment, requiring the detector assemblies to be maintained at 18°C +/-1°C.Image: CASHE hosts a central electronics box that is responsible for providing the high-voltage power supply to the detectors and accept amplified signals from all detectors and anti-coincidence monitors. Data from the instrument is delivered to the satellite platform through LVDS high-speed interfaces and a 1553 data bus is used for relaying housekeeping telemetry to the satellite and accepting commands for instrument actuation. The electronics box also receives a pulse-per-second signal for time synchronization as well as a 5 MHz signal from an ultra-stable oscillator to provide the precise timing needed for X-ray measurements.Testing of the flight model of HE showed the NaI scintillators can make measurements in an energy range of 16-350 keV when the instrument operates in normal mode while the CsI in GRB mode can detect gamma-rays at energies of 130 keV to 3 MeV. (In normal mode, NaI events are good events and in GRB mode, only CsI events are good events.) HE achieves a source location accuracy of under 1 arcmin, an angular resolution better than 5 arcmin and a time resolution better than 25µs.ME Structure - Image: HXMT ProjectThe Medium-Energy X-Ray Telescope uses a total of 1,728 Silicon-PIN diodes as detectors, facilitated in three modules installed on the optical bench of the HXMT observatory and creating a total active area of 952cm², sensitive in the 5-30 keV range.ME also hosts three different Fields of View - the main FOV is 1 x 4° to capture data on targets, the broad FOV for background measurements is 4 x 4° and a fully blocked detector group provides dark current measurements for calibration.The large number of PIN diodes actively gathering data requires an elaborate read out system using 54 Application Specific Integrated Circuits.ME Detector Box - Image: HXMT ProjectME employs a layered architecture with the Main Electronics Box at the top, interfacing via high-speed LVDS with the three Detector Boxes containing six Modules, each reading out 32 Si-PIN pixels. Four pixels are facilitated in one ceramic package (active area of 56.25mm² each), creating a total of 432 pixel units installed on ME. The data acquisition circuit is controlled by Field Programmable Gate Arrays, allowing the acquisition to be tweaked during the mission.The 32-channel ASIC chips form the central part of the read-out chain and are in charge of collecting raw signals from the pixels, amplifying the electrical signals, digitizing the output and transmitting the pre-processed signal to the Main Electronics Box. The use of ASIC technology allows ME to operate at a very high time resolution of 255µs.Collimators atop each pixel set its field of view and all pixels are connected to active thermal control systems to maintain a temperature of -5 to -50 degrees Celsius to lim it the effects of dark currents.LE Detector Box - Image: HXMT ProjectThe Low-Energy X-Ray Detector (LE) is focused on sky survey and pointed observations in the soft X-ray range of 0.7 to 15 keV. It is different from the detectors on Chandra and XMM-Newton that cover a similar energy range but use grazing incidence optics. Instead, HXMT utilizes collimators to shield the photons outside the field of view.LE comprises three detector boxes holding Swept Charge Devices that work in a continuous read-out mode, recording the energy and arrival time of incident photons to achieve a higher time resolution than traditional CCD detectors which collect photons over a pre-programmed exposure time. With its good energy and exceptional time resolution, LE is expected to make a significant contribution to X-ray astronomy.The LE instrument hosts three identical detector boxes installed on the +Z side of the main payload section and a central electronics box within the payload module. The three boxes, similar to ME, are installed with an angle of 120 degrees to each other to enable the modulation of the signals from the three boxes to extract the image information through a restoration technique like direct demodulation.LE Detector Elements - Image: HXMT ProjectThe Swept Charge Devices (SCDs) have the ability to convert the energy of an incident soft-X-ray photon into electric signals that are proportional to that photon's energy. These electric signals are transmitted to the electronics box wh ere they are converted to a digital representation including the event energy and arrival time. Payload data is sent to the spacecraft via LVDS and commanding / housekeeping data exchange is completed through a 1553 link.Within each detector box are eight collimators that set the field of view for each corresponding detector unit of 2×2 pixels, making for a total of 32 SCD chips per detector box and 96 in total for an active area of 384cm². Optical blocking filters, remainder-proof films and thermal support systems like heat pipes are also facilitated within each detector box. The electronics for each box reside directly beneath it to accept the raw signals fr om the individual pixels for amplification, digitization and time-tagging.Image: HXMT ProjectLE employs pointing observation and survey collimators with combined wide (4 x 6°) and narrow (1.6 x 6°) FOVs plus blocked pixels for background measurements and an All-Sky Monitoring collimator creates a 50~60° x 2~6° Field Of View for one pixel array per detector to support the all-sky survey that is a core objective of the HXMT mission. Of the 32 SCD pixels in each detector box, 20 have narrow FOVs, six have wide FOVs, four are All-Sky Monitor pixels and two are blocked detectors acting as calibration sources.LE achieves an energy resolution of 140 eV and a time resolution of 1ms. Its detectors are maintained between -30 and -80°C.HXMT will operate in an orbit of 550 Kilometers at an inclination of 43 degrees, designed for the mission's observation objectives and to reduce the overall radiation influx to reduce backgrounds.
ЦитатаЦзюцюань, 15 июня /Синьхуа/ -- В четверг утром Китай запустил свой первый рентгеновский космический телескоп для наблюдения за черными дырами, пульсарами и гамма-всплесками. Телескоп был выведен на орбиту ракетой-носителем "Long March - 4B" /"Чанчжэн - 4Б"/, запущенной с космодрома Цзюцюань /пров. Ганьсу, Северо-Западный Китай/.
ЦитатаЦзюцюань, 15 июня /Синьхуа/ -- В четверг в 11:00 Китай запустил свой первый рентгеновский космический телескоп для наблюдения за черными дырами, пульсарами и гамма-всплесками.2,5-тонный рентгеновский телескоп "Insight" был выведен на орбиту на высоте 550 км над поверхностью Земли ракетой-носителем "Long March - 4B" /"Чанчжэн - 4Б"/, запущенной с космодрома Цзюцюань, расположенного в пустыне Гоби на северо-западе Китая.Телескоп поможет ученным лучше изучить эволюцию черных дыр, мощные магнитные поля и внутреннюю часть пульсаров.С его помощью ученые также намереваются изучить способы использования пульсаров для навигации космических кораблей, а также отыскать гамма-всплески, соответствующие гравитационным волнам.Как ожидается, благодаря усилиям нескольких поколений китайских ученных, телескоп "Insight" будет содействовать развитию космической астрономии и технологий зондирования с помощью рентгеновских лучей в Китае.
Цитатаche wi пишет: телескоп "Insight"
ЦитатаCAS 4A & CAS 4B amateur radio payloads piggybacked on Chinese imaging microsatellites OVS 1A & OVS 1B
Цитата Andrew Jones @AJ_FI 2 ч. назадChina's tracking station at Kashi in Xinjiang picked up the first data from #HXMT at 16:45:25 Beijing time (08:45 UTC) today.
ЦитатаChina receives data from first X-ray space telescopeSource: Xinhua | 2017-06-16 20:49:00 | Editor: An BEIJING, June 16 (Xinhua) -- China Friday received the first package of data from its x-ray space telescope launched Thursday, according to the Institute of Remote Sensing and Digital Earth of the Chinese Academy of Sciences (CAS).The package of high quality data with a total size of 2.1 gigabytes was received by the remote sensing satellite station in northwest China's Kashgar, before being transferred to the CAS National Space Science Center.The ground stations in Beijing's Miyun District and south China's Sanya also tracked the signals from the telescope. Скрытый текст: Weighing 2.5 tonnes, the Hard X-ray Modulation Telescope, dubbed Insight, was launched via a Long March-4B rocket from Jiuquan Satellite Launch Center in northwest China's Gobi Desert at 11 a.m. Thursday.In the following five days, other components of Insight will start working in succession.After five months of in-orbit tests and calibrations, the telescope will be officially put into use to conduct broadband x-ray space observations. Its main tasks are to observe black holes, pulsars and gamma-ray bursts.Kicking off in March 2011, the Insight project was jointly carried out by the State Administration of Science, Technology and Industry for National Defence and the CAS, and is a crucial part of China's high-energy astrophysics space research.
Цитата ChinaSpaceflight @cnspaceflight 9 ч назад【珠海一号】OVS-1A/B视频卫星首批卫星影像数据----梵蒂冈、日本大阪、汉城空军基地。 Скрытый текст:
Цитата【Zhuhai-1】 OVS-1A / B video satellite first satellite imagery data - Vatican City, Japan Osaka, Seoul Air Force Base..
ЦитатаЧжухай-1 ОВС-1A / B спутниковых данных видео первого спутника изображения - Ватикан, Осака, Сеул Air Base.
Цитата ChinaSpaceflight @cnspaceflight 9 ч. назад【珠海一号】大连机场 https://youtu.be/JZtYjERn9mM
Цитата【Zhuhai-1】 Dalian Airport
Цитата【Чжухай-1】 Аэропорт Далянь
Цитата ChinaSpaceflight @cnspaceflight 9 ч. назад图片放大后
ЦитатаAfter the picture is enlarged
ЦитатаЕсли фото увеличить
ЦитатаChina's first space observatory turns on X-ray detectorsAndrew Jones2017/06/26The main detectors on China's first space observatory, the Hard X-ray Modulation Telescope (HXMT), have been powered up as the satellite enters a period of on-orbit testing.HXMT, also known as '慧眼' (Huiyan) or 'Insight', was launched fr om the Jiuquan Satellite Launch Centre atop a Long March 4B rocket on June 15. Скрытый текст: HXMT, or Huiyan, lifts off from Jiuquan at 11:00 on June 15, 2017. (Photo: Courtesy of Qiang Wang, Chinese Academy of Sciences)The probe's three sets of main detectors have now been booted, according to the Institute of High Energy Physics (IHEP).The low-energy detectors (LE) and mid-range detectors (ME) were switched on on June 19, with the high-energy detector (HE) following on June 21.Together they will collect highly energetic x-rays emitted by black holes, neutron stars and other phenomena across a range of 1-250 kiloelectron volts (keV).Black holes and neutron stars are the main sources of cosmic X-rays, but these can only be seen from space, as the Earth's atmosphere absorbs X-rays.Zhang Shuangnan, principal investigator of the project, says that HXMT will survey the Galactic plane to create a high precision x-ray map of the sky.The probe's wide range of energy coverage means it may pick up previously undiscovered black holes in the Milky Way, and perhaps even new types of objects.Above: The HXMT satellite under development (CAST).HMXT is currently orbiting between 538 and 547 km above the Earth, inclined by 43 degrees, wh ere it is expected to operate for at least four years.It joins a number of X-ray observatories in orbit, including NASA's Chandra and NuSTAR, and XMM-Newton, launched by the European Space Agency.HXMT will also look for the electromagnetic counterparts to gravitational waves, which were first detected by LIGO in 2015, and gamma-ray bursts (GRBs) up to energies of 3,000 keV. Another potential use of the satellite is to explore the mechanisms of neutron star and pulsar timing, following on from the cutting edge XPNAV-1 satellite launched last autumn, potentially working in concert with the Five Hundred Metre Aperture Spherical Telescope (FAST) in Guizhou Province. Dawn of Chinese space scienceHXMT was the fourth and final launch of a first batch of space science missions developed by the Chinese Academy of Sciences (CAS), follows the DAMPE dark matter probe, the Shijian-10 retrievable microgravity experiment satellite, and the pioneering QUESS quantum science satellite.A second batch of five missions are already under development, with launches expected around 2020.They are the space-weather observatory mission in collaboration with the European Space Agency (SMILE), a global water cycle observation mission (WCOM), the Magnetosphere, Ionosphere and Thermosphere mission (MIT), the Einstein Probe (EP), and the Advanced Space-based Solar Observatory (ASO-S).
ЦитатаInsight-HXMT Sets Limits in New Gravitational Wave EventOct 16, 2017Insight-HXMT, China's first X-ray astronomical satellite, has made an important contribution to gravitational wave astronomy, by setting a strict upper limit on electromagnetic radiation produced during a recently discovered gravitational wave event. Скрытый текст: The Laser Interferometer Gravitational Wave Observatory (LIGO) and the European Gravitational Observatory Virgo announced on Oct. 16th 2017 the discovery of the gravitational wave event GW170817.It contrasts with four previous gravitational wave events, which were caused by the merging of black holes, and this event is thought to have been created by the merging of two neutron stars. It is widely believed that this kind of new gravitational wave event can also produce strong electromagnetic (EM) emission at the time of merger.An artist's impression of two stars orbiting each other (left). The orbit shrinks as the system emits gravitational waves (middle). When the stars merge (right), there is a resulting powerful emission of gravitational waves. (Image by NASA)Dozens of observatories joined in an observation campaign to search for the EM counterpart of this event, searching at frequencies fr om radio to very high energy gamma-rays. Insight-HXMT, which was launched on June 15th 2017, has made an important contribution by setting a stringent upper limit on its prompt emission flux in the 0.2-5 MeV range.Artist's impression of the Insight-HXMT satellite in space (Image by IHEP)Only four X-ray and gamma-ray telescopes (Fermi, INTEGRAL, Insight-HXMT, and Konus-Wind) were monitoring the sky region of GW170817 when the event took place. Of these, Insight-HXMT has the largest detection area and best time resolution in the 0.2-5 MeV range.About two seconds after the gravitational wave event, a weak short gamma-ray burst (GRB 170817A) independently triggered the Fermi Gamma Burst Monitor (GMB). The GBM localization is broadly consistent with the gravitational wave location given by the LIGO detector. Soon after, this gamma-ray burst was confirmed by offline analysis of data from the INTEGRAL satellite's SPI-ACS system.However, different from theoretical predictions, the emission of GW170817 is weak and soft, and so the flux in the MeV energy band is extremely low. Neither Insight-HXMT nor any of the other telescopes has detected any significant emission in this energy range.Insight-HXMT then set the most stringent MeV flux upper lim it, which is important for constraining the overall properties of GW170817. The observational results of Insight-HXMT will be published in a paper on the multi-messenger astrophysics of GW170817 that will be appear in The Astrophysical Journal Letters, and in a separate paper to be published in SCIENCE CHINA Physics, Mechanics & Astronomy.According to Einstein' s theory of general relativity, the merging (coalescence) of two compact stars is able to create ripples in space-time known as gravitational waves. On September 14th, 2015, LIGO detected the first gravitational event. In honor of this achievement, the leaders of the LIGO experiment, Rainer Weiss, Barry Barish, and Kip Thorne were awarded the 2017 Nobel Prize in Physics.(Editor: LIU Jia)
Цитатаuncle_jew пишет: Хм, а ведь раньше считалось, что гамма-вспышки - вещь направленная, и мы их видим только если Земля находится на пути луча. И что именно поэтому они кажутся такими яркими - энергия не во все стороны излучается.А тут обнаружили гамма-вспышку прям у первого же известного слияния нейтронных звёзд.Теория поменялась и теперь снова считают, что гамма-вспышки излучаются во всех направлениях? Потому что иначе было бы бессмысленно определять "верхнюю границу" мощности - т. к. она зависит от положения Земли относительно направленности луча.
ЦитатаChina's X-ray space observatory completes on-orbit testing after observing neutron star collision by Andrew Jones | Dec 01, 2017 12:09 | CHINA ● BEIJING ● ITALYA rendering of the Hard X-ray Modulation Telescope in orbit. NSSCChina's first space telescope, the Insight X-ray observatory, has completed a five-month on-orbit testing phase, during which time it joined the global hunt for light fr om the collision of two neutron stars.Zhao Jian, deputy director of the system engineering department of the State Administration of Science, Technology and Industry for National Defence (SASTIND), said at a review meeting on November 28 in Beijing that on-orbit testing had been satisfactorily completed and that most of the indicators exceeded the design targets and completed high-quality on-orbit testing with excellent results. Скрытый текст: The Hard X-ray Modulation Telescope (HXMT), also named Huiyan or 'Insight' upon launch on June 15 this year, was designed to study the properties of transient X-ray sources in great detail and the circumstances in which emissions are generated.The telescope will now survey the Galactic plane to create a high precision X-ray map of the sky, and in doing could confirm previously undiscovered black holes in the Milky Way, and perhaps even new types of objects.At the meeting, arranged by the Chinese Academy of Sciences (CAS) and SASTIND at the Institute for High Energy Physics (IHEP), the review team expressed that it has high hopes that Insight-HXMT and the research team will seize the opportunity to achieve unforeseen, breakthrough scientific results.The mission has already had an impact. Insight-HXMT was recently involved in the global race to make observations of the electromagnetic counterparts to the gravitational waves unleashed by the collision of two neutron stars, with its observations putting a strict upper lim it on electromagnetic radiation emitted and helping to confirm the unexpectedly weak and soft nature of the gamma ray burst. The event was also observed by Chinese Antarctic telescopes.The August 18 optical signal observation of the gravitational wave event GW170817 made by AST3-2. Purple Mountain ObservatoryAnother potential use of Insight-HXMT is to explore the mechanisms of neutron star and pulsar timing, following on from the cutting edge XPNAV-1 satellite launched last autumn, potentially working in concert with the Five Hundred Metre Aperture Spherical Telescope (FAST) in Guizhou Province.Wang Yifang, director of IHEP, thanked those at all levels at SASTIND and CAS for their support, and stressed that the institute would strive to improve the scientific output from Insight-HXMT. He also stated his strong support for future X-ray astronomy missions, including the enhanced X-ray Timing and Polarimetry Mission (eXTP), a space science mission designed to study the state of matter under extreme conditions of density, gravity and magnetism which is proposed for launch before 2025 and involves European partners.Insight-HXMT initially had problems with funding, having been proposed in the 1990s but only gaining the necessary funding from the China National Space Agency (CNSA) and CAS in 2011, joining the DAMPE-Wukong dark matter probe, Shijian-10 retrievable probe and QUESS-Mozi quantum space science satellite in a first batch of Chinese space science missions.These have all now been declared successful, with a new round of missions now beginning. DAMPE on Wednesday saw its its first results released, bringing a hint of an indirect detection of elusive dark matter.Assistance from ItalyThe University of Ferrara in Italy has been involved with the HXMT team by supporting ground calibrations on the instruments at its LARIX X-ray facility.Initial interest from China in collaborating with Italy came from the success of BeppoSAX, an Italian-Dutch X-ray astronomy satellite, says Professor Filippo Frontera at the Department of Physics and Earth Sciences at Ferrara.Both sides are now looking to continue working together, both relating to the findings of HXMT, such as unidentified high energy sources that may be discovered during the frequent Galactic plane surveys and the gamma-ray counterparts of gravitational signals, and beyond to other fields of mutual interest.
ЦитатаКитай ввел в эксплуатацию свою первую орбитальную рентгеновскую обсерваторию HuiyanПЕКИН, 30 января. /ТАСС/. Китайский спутник Huiyan официально введен в эксплуатацию и будет использоваться в качестве первой китайской рентгеновской обсерватории для исследования Вселенной. Об этом сообщило во вторник Государственное управление науки, технологий и промышленности для оборонных нужд КНР."Космический аппарат предназначен для исследования целого ряда космических явлений, в том числе черных дыр и пульсаров (нейтронных звезд)", - отмечается на сайте ведомства.Huiyan был запущен 15 июня 2017 года с космодрома Цзюцюань (северо-западная провинция Ганьсу). За это время он успешно прошел орбитальные испытания и был признан пригодным для использования для реализации ряда ключевых научно-технических проектов стратегической значимости.
ЦитатаChina's space telescope opens new window to observe black holes Source: Xinhua| 2019-10-26 22:43:36|Editor: Shi Yinglun XIAMEN, Oct. 26 (Xinhua) -- China's first X-ray space telescope has helped scientists open a new window to observe and better understand bizarre celestial bodies like black holes and neutron stars.The Hard X-ray Modulation Telescope (HXMT), dubbed Insight, sent into an orbit of 550 km above the Earth on June 15, 2017, has detected areas that are probably the closest to the black holes so far, shedding light on the basic properties of black holes and neutron stars and the behavior and radiation of matters near the strong magnetic and gravitational fields, said Lu Fangjun, deputy chief designer of the satellite.The research team from the Institute of High Energy Physics of the Chinese Academy of Sciences announced some of the findings of the space telescope at the first China Space Science Assembly, which opened Saturday in Xiamen, east China's Fujian Province.The satellite has conducted high precision and high-frequency observations on the binary star systems formed by a black hole and a normal star, or a neutron star and a normal star. When the matter of the normal star, driven by the strong gravitation, falls into a black hole or neutron star, it is accelerated and heated during the process, emitting strong X-rays, said Lu."We call them X-ray binary systems, which are regarded as natural laboratories of extreme physical conditions," said Lu.Scientists study many phenomena that they cannot replicate on Earth by observing such systems and might learn more about the characteristics of black holes and neutron stars from the X-rays.The HXMT has found a quasi-periodic change of the high energy X-rays emitted by the matter near black holes and neutron stars, Lu said.Compared with X-ray astronomical satellites of other countries, HXMT has a larger detection area, broader energy range and more effective working time. These give it advantages in observing black holes and neutron stars emitting bright X-rays, according to Lu.During its over two-year operation in orbit, the telescope has conducted more than 1,000 observations, sending back 2TB of scientific data. The satellite was also used to search for gamma-ray bursts corresponding to gravitational waves and test pulsar navigation.
ЦитатаКитайская обсерватория HXMT дает ученым новые возможности для исследования черных дыр 2019-10-29 20:25:55丨Russian.News.Cn Сямэнь, 29 октября /Синьхуа/ -- Первая китайская космическая обсерватория HXMT открыла ученым новые горизонты для наблюдения черных дыр и нейтронных звезд.Обсерватория HXMT или Insight - это модуляционный телескоп жесткого рентгеновского диапазона, который был выведен на орбиту высотой 550 км над поверхностью Земли 15 июня 2017 года.При помощи этого космического аппарата астрономы исследовали районы, находящиеся на еще более близком расстоянии от центра черных дыр, что пролило свет на основные свойства черных дыр и нейтронных звезд, а также излучение вблизи сильных магнитных и гравитационных полей, сообщил заместитель главного конструктора проекта HXMT Лу Фанцзюнь.Исследовательская группа из Института физики высоких энергий Академии наук Китая объявила о ряде открытий, сделанных при помощи HXMT, на 1-й Китайской ассамблее по вопросам космической науки, состоявшейся на днях в городе Сямэнь провинции Фуцзянь на востоке Китая.Обсерватория провела высокоточные и высокочастотные наблюдения двойных звезд, которые состоят из черной звезды или нейтронной звездой с связанной гравитацией звездой-компаньоном. Попадая в черную дыру или к нейтронной звезде, вещество звезды-компаньона ускоряется и нагревается, испуская сильные рентгеновские лучи.В ходе наблюдения названных систем в диапазоне рентгеновского излучения, ученые исследовали явления, которые невозможно воспроизвести на Земле, и постарались узнать больше о характеристиках черных дыр и нейтронных звезд.Обсерватория HXMT открыла квазипериодическое изменение высокоэнергетического рентгеновского излучения вблизи черных дыр и нейтронных звезд, проинформировал Лу Фанцзюнь.По сравнению с иностранными аналогами, HXMT способна вести наблюдение в более широкой зоне и в широком энергетическом диапазоне, добавил он.За прошедшие два с лишним года обсерватория отправила обратно на Землю данные наблюдений в объеме 2 ТБ. HXMT также использовали для поиска гамма-всплеска и гравитационных волн и тестирования пульсарной навигации.
ЦитатаChina Focus: Chinese satellite explores mysterious signals in universe Source: Xinhua| 2021-02-19 19:00:54|Editor: huaxia BEIJING, Feb. 19 (Xinhua) -- China's Hard X-ray Modulation Telescope (HXMT), the country's space science satellite also known as Insight, has found that a fast radio burst (FRB) signal detected last year came from a magnetar in the Milky Way, Chinese scientists announced Friday.The discovery marked a milestone in understanding the nature of the mysterious signal emanating from the universe, the scientists said.The research was conducted jointly by scientists from the Institute of High Energy Physics (IHEP) under the Chinese Academy of Sciences, Beijing Normal University, University of Nevada Las Vegas, Tsinghua University and other institutions. The findings have been published in the latest issue of Nature Astronomy. Скрытый текст: In 2007, scientists detected bursts of extremely powerful radio waves in the sky lasting no more than a few milliseconds. The mysterious signal became known as FRBs.Dozens of FRBs have been detected in the following decade, and astronomers have been trying to figure out what causes FRBs. Some reports even speculated that alien civilization could have been beaming FRBs to Earth.One theory is that FRBs may come from magnetars, a type of neutron star. All neutron stars are the collapsed core of a dead star, not massive enough to become a black hole, while magnetars also have a shockingly powerful magnetic field.Until last April, every known FRB came from outside the Milky Way, making them near impossible to study.On April 28, 2020, two telescopes in North America, namely the Canadian Hydrogen Intensity Mapping Experiment (CHIME) and the U.S. Survey for Transient Astronomical Radio Emission 2 (STARE2) picked up a powerful millisecond-duration burst in our Milky Way. It has since been named FRB 200428, and was listed as the top 10 breakthroughs of 2020 by both Science and Nature.FRB 200428 was located about 30,000 light-years away, roughly the same direction as magnetar SGR J1935+2154. The magnetar was acting up when the FRB 200428 was detected, emitting bursts of x-rays and gamma rays.Although scientists believe that they had pinpointed the origin of FRB 200428, a final piece of the puzzle is still missing, which is needed to confirm SGR J1935+2154 produced the radio bursts."It is pure luck that China's space telescope caught the significant signal," said Zhang Shuangnan, lead scientist of HXMT, in an interview with Xinhua.Zhang added that China's HXMT temporarily changed its observation plan last April to focus on SGR J1935+2154. Seven hours after the ground control sent the observation command, HXMT detected a very bright x-ray burst from SGR J1935+2154 which was about 8.6 seconds before FRB 200428.Zhang said the time difference is consistent with the time delay of the radio signal due to the interstellar medium, indicating that the x-ray and radio bursts are from the same explosion, and it found that two spikes of the X-ray burst are the high energy counterpart of FRB 200428.Compared with other space telescopes, HXMT provided the most detailed temporal and spectral information in understanding FRBs and magnetars, Zhang noted. Скрытый текст: "The discovery is not the end of FRB stories, but the start of a new era," said Zhang.The enhanced X-ray Timing and Polarimetry (eXTP) satellite developed by IHEP and many other domestic and international partner institutions, has entered phase-B (design phase), after more than 10 years of preliminary study and key technology development, he added. It will enable scientists to study FRBs, neutron stars and black holes from other galaxies."The universe is much stranger than we think," said Shrinivas R. (Shri) Kulkarni, George Ellery Hale Professor of Astronomy and Planetary Science at California Institute of Technology, in an interview with Xinhua via Zoom. He called on scientists to keep on exploring.Kulkarni added that building astronomy telescopes is very expensive and no country can do astronomy all by itself, noting that China's telescopes like FAST and HXMT have become driving engines for new discoveries."I am very happy for my Chinese colleagues that your government is supporting basic science. This is very exciting that a large country like China is contributing enormously to modern science," he said..Since its launch on June 15, 2017, HXMT has achieved a series of important scientific results on black holes, neutron stars and other objects or phenomena. The calibration of the detectors on board was supported by the National Institute of Metrology, Ferrara University in Italy and the Max Planck Institute for Extraterrestrial Physics.