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China Outer Space Science, Technology and Explorations: News & Updates

New communications satellite company awaits approval

2017-10-31 09:30

China Daily Editor: Liang Meichen

China Aerospace Science and Industry Corp, a major space contractor, is considering the establishment of a satellite company to tap the space-based communications market, according to a project insider.

Tan Qianhong, Party chief of China Space Sanjiang Group, a CASIC subsidiary in Hubei province, said Sanjiang has submitted a plan on the proposed satellite firm to CASIC and is waiting for approval.

The new entity would focus mainly on the research, development and launch of small satellites that would operate in low orbit and provide narrowband communications service, Tan told China Daily in an exclusive interview. Tan spoke on the sidelines of the 19th National Congress of the Communist Party of China, to which he is a delegate.

"General Secretary Xi Jinping has stressed that China's modernization drive will not succeed without the completion of informatization," he said. "Space-based infrastructure is a pillar of the information industry. The new company would be tasked with forming a satellite constellation to boost space-based communications."

Informatization is the development of an information-based economy.

The network would offer coverage to users at sea or in remote regions that have poor access to ground-based communications services, according to Tan. He said the proposed firm would have a team of satellite designers but would procure others' satellites if they have better cost-performance ratios.

Tan said Sanjiang also would continue to improve the capabilities of its Kuaizhou-series carrier rockets, a major product of the company, and use them to acquire more commercial space contracts.

In China, the commercial space industry generally includes development and production of spacecraft not sponsored by the government as well as non-State launch activities. While China has a long history of space exploration, commercial involvement in space is a new idea that is gaining popularity among State-owned space contractors and private enterprises in the wake of the country's rocketing demand for space-based services.

"We will strive to reduce our rockets' costs and to strengthen their capacities. We will also introduce private capital and partners in the rockets' production to optimize the outsourcing and marketing work," he said.

Sanjiang began to develop Kuaizhou-series solid-fuel rockets in 2009 in hopes of presenting a low-cost, quick-response rocket family to the commercial launch market. It has launched three of the rockets-two Kuaizhou 1 models and one Kuaizhou 1A.

In 2018, Sanjiang plans to launch four Kuaizhou 1A rockets within one week. Each will lift a remote-sensing satellite into orbit for a client. The missions are expected to set a world record for launch frequency for a single model of carrier rocket, the company said.

A new-generation rocket, the Kuaizhou 11, is being tested and will make its first flight next year, sending six satellites into orbit, according to Sanjiang.

The Kuaizhou 11 will have a liftoff weight of 78 tons and will be capable of placing a payload of 1 metric ton into a sun-synchronous orbit at an altitude of 700 kilometers, or a 1.5-ton payload into a low-Earth orbit.

http://www.ecns.cn/2017/10-31/278994.shtml
 
China to test reusable space launch vehicles in 2020
(People's Daily Online) 14:46, October 31, 2017

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China plans to test its own reusable space launch vehicles in 2020, with an ultimate goal of decreasing the current space transportation cost by 90 percent, as well as reducing the time for launch preparations.

“The launch of our reusable space vehicles will take place in 2020, after which more tests and experiments will be carried out. The space vehicles are designed to be reused for over 20 times, reducing transportation costs by 90 percent,” Chen Hongbo, director of the research center at the China Aerospace Science and Technology Corporation, told the Science and Technology Daily.

Chen also noted that the preparation time for the launch of a traditional rocket may take as long as several months, while the reusable space vehicles are expected to be launched within a day.

“Compared to other reusable space vehicles, for instance, America’s Falcon 9, our vehicles can recover two stages of the rocket, while currently only the first stage of the Falcon 9 can be retrieved,” Chen added.

According to Science and Technology Daily, China is set to complete all research projects and tests regarding reusable space launch technologies and is expected to be the first country in the world that can realize the full reusability of space launch vehicles.
 
New video satellites ready for launch pad

2017-10-31 14:22

chinadaily.com.cn Editor:Li Yan


Researchers work on the JILIN-1 Agile Video Satellite. (Photo/for China Daily)

Three new JILIN-1 Agile Video Satellites produced by the Chang Guang Satellite Technology Co Ltd left the factory on Friday in Changchun, Northeast China's Jilin province, according to the company.

The company plans to send them into space in November from the Taiyuan Satellite Launch Center, which will bring the number of satellites manufactured and launched by the company to eight.

Researchers greatly improved the temporal resolution of the new satellites, reducing the visiting time (the length of time it takes for the orbiting satellite to fly by a certain point) from three days to one day, which will greatly upgrade service ability and promote marketing in sensing satellites.

According to the company, it will have 10 satellites operational by the end of 2017, and 60 satellites in service by 2020, which will ultimately make it possible to offer a 10-minute revisit capability of satellites anywhere in the world.

The first group of the JILIN-1 satellite networking project, China's first self-made, high-resolution remote-sensing satellite for commercial use was launched and put into service in October 2015.

It is China's first self R&D high-resolution commercial satellite, China's first self R&D integral satellite and China's first R&D high definition video satellite. It is also the first satellite to be named after a province.

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‘Universal’ business: China eyes bringing down rocket launch price to $5,000 per kilogram
By Jiang Jie (People's Daily Online) 10:41, November 02, 2017

As in other business fields, China’s commercial space sector will soon see its price advantage as it eyes to bring down the price of rocket flights to as low as $5,000 per kilogram.

Speaking at an aerospace forum in Beijing on Wednesday, Yang Baohua, vice general manager of China Aerospace Science and Technology Corporation (CASC), revealed that the company is ready to provide cheaper and faster low-earth orbit rocket launches. The price could be as low as $5,000 per kilogram and the pre-launch preparation will only need a week.

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(File photo of Long March-6 rocket. Courtesy of CASC)​

It will cost $5,000-6,000 for those eyeing sun-synchronous orbit and the preparation period will take about 10 days. For geostationary transfer orbit, the price will stay between $8,000 and $10,000, according to Yang.

Meanwhile, CASC might start providing services for sea launches in 2018. It is also seeking opportunities to offer commercial launches at low altitude.

On worldwide communication, Yang shared the company’s blueprint to set up worldwide mobile broadband service by 2026, which means the deployment of more than 300 satellites in 18 different orbits.

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(File photo of Long March-11 rocket. Courtesy of CASC)​
 
China holds leading position in research of space-based solar power
By Sun Wenyu (People's Daily Online) 14:57, November 02, 2017

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An artist's rendition of a space-based solar power station

China now holds a leading position in the research of space-based solar power after decades of research which has narrowed the gap between itself and leading countries, Li Ming, research fellow of China Academy of Space Technology (CAST), told Science and Technology Daily on Nov. 1.

China is expected to be the first country to build a practical space-based solar power station, as long as it continues investing in research and development, Li added.

Wang Li, another research fellow with CAST, noted that both Chinese and foreign experts are optimistic about China’s leading ability in this field.

Compared with traditional fossil energy, which has been increasingly exhausted and is responsible for severe environmental issues, space-based solar power is more efficient, sustainable, and clean. It can generate as much energy as a ground-based nuclear power plant.

However, the construction has long been a challenge for scientists, because its weight and size are way beyond the current carrying-capacity of spacecraft.

The US, Japan, and Russia have all made huge investment in this area, and the space departments of India, South Korea, and Europe are also conducting related research.

Taking space-based solar power as a key research program since 2008, China has made a number of major breakthroughs in wireless energy transmission and proposed various energy-collecting solutions.

The country has become a leader in and a major promoter of the development of space-based solar power.

Wang believes that leading in this area is an opportunity for China to further narrow its gap between itself and other major space powers.

Space-based solar power will ease environmental and energy pressure in China, and also spur the country’s innovation and emerging industries, Wang added.
 
China aerospace giant working on satellite clusters for global communications
By Zhao Yusha Source:Global Times Published: 2017/11/2 22:13:40

China missile company works on global communications
China's giant State-owned aerospace company is eying the commercial end of the industry, with the idea of setting up a satellite company that can create a global Internet of Things (IoT).

Tan Qianhong, head of Sanjiang Space Industry Group, a China Aerospace Science & Industry Corporation (CASIC) subsidiary research institute in Hubei Province, said that the new company will be in charge of a small low-earth-orbit satellite to form a group of satellites for narrow-band communications and improving communication in remote areas and at sea, according to a CASIC statement sent to the Global Times on Thursday.

"The small low-earth-orbit satellite constellations allow for Internet access and communications everywhere on the planet, including airplanes and ocean-going ships," said Wang Yanan, chief editor of Aerospace Knowledge magazine.

Tan explained that researchers will have their own satellite design team and will buy satellites from outside, while the institute said that it already handed over a company plan to CASIC and is waiting for the results.

CASIC is the country's largest tactical and air defense missile manufacturer and therefore, the commercial end of the aerospace business is a new field.

"CASIC already has advanced rocket and missile technology and it is just taking one step further in exploring the satellite market, which could bring market value and greater use of their missile and rocket technology," said Wang.

A first Xingyun satellite project, developed by the CASIC research institute, was successfully sent aloft in January, China News Service reported.

This Xingyun project bears some similarities with the new company proposal because it also contained plans for narrow-band satellite constellations, China News Service reported.

Network receipt terminals can be embedded in a number of devices for the global mobile IoT, or existing smart phones to allow users to send or receive text messages from any location.

In March, CASIC announced plans for a network of 156 mini-satellites for greater global broadband coverage. It will be China's first low-orbiting satellite network, about 1,000 kilometers above the earth, as part of a wider commercial space development project, the Xinhua News Agency reported.

Plans call for sending the first satellite aloft before 2018, and four more by 2020, for a constellation. By the end of the 14th Five-Year Plan (2021-25), all 156 satellites will be in operation, said Xinhua.

The institute also said that it had developed the country's first reflection-control equipment for the satellites, for optical communications by changing a laser's direction and to point it at another satellite, without changing the satellite's position.
 
China expected to complete first sea launch for commercial payloads in 2018
By Sun Wenyu (People's Daily Online) 16:38, November 03, 2017

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SpaceX Falcon 9 rocket lands on a drone ship at sea. (File photo)

China is expected to complete its first sea launch for commercial payloads in 2018, said Yang Baohua, vice general manager of China Aerospace Science and Technology Corporation (CASTC).

Yang made the remarks at an annual academic conference on space science held from November 1 to 2 in Beijing.

The service will also be provided in other regions in addition to its four major sites in Jiuquan, Taiyuan, Xichang, and Wenchang, Yang noted.

At the conference, Yang introduced the company’s experience, competence, and advantages, as well as its on-going commercial aerospace programs, and also evaluated the prospects of the commercial space industry.

“CASTC is dedicated to offering various commercial launching solutions to meet the market demands of low cost and fast preparation,” Yang said.

Key technological tests will be conducted for the sea launch of the Long-march rocket family this year, according to Tang Yagang, deputy director of carrier rocket development at the China Academy of Launch Vehicle Technology.

The commercial service is expected to be available for international users in 2018. By then, the Long-march rockets will be able to send 500-kilogram satellites to an altitude of 500 kilometers above Earth, at an inclination of 0-10 degrees.

In recent years, with the growing demand for launching near-equatorial and low-inclination satellites from countries near the equator, sea launch service has become an area of fierce competition among space powers.

http://en.people.cn/n3/2017/1103/c90000-9288601.html
 
China’s rockets for the new age broaden space development
By Zhang Qiyong Source:Global Times Published: 2017/11/6 22:58:39

The Long March 2C, China's new generation of carrier rockets, will carry a new aircraft aloft in 2018 and an expert said it is of major significance for China's space development.

The new aircraft, a Yuanzheng-1S, is able to carry different types of satellite into orbit. Its design work was finished in March, so it can be used for Sun-synchronous orbital missions next year, the China Academy of Launch Vehicle Technology (CALVT) said on its website.

The Yuanzheng-1S is a simpler commercial version of the Yuanzheng-1 and is used for short missions and mid-to-low-Earth orbit, Wang Mingzhe, a research fellow from the Beijing Institute of Astronautical Systems Engineering said on the CALVT release.

Yuanzheng-1, dubbed the "space shuttle bus," has been launched into the earth orbit by the Long March-7, Wang Xiaojun, chief commander of the Long March-7 program, told a press conference, the Xinhua News Agency reported in June 2016.

China has developed 3 upper stages for carrier rockets - the Yuanzheng-1, Yuanzheng-1A, and Yuanzheng-2, Xinhua reported.

"The upper stage has the ability to send satellites into orbit, especially medium-to-high orbits. It is an independent module that can be loaded on different carrier rockets," Song Zhongping, a Phoenix TV commentator and military expert, told the Global Times on Monday.

The upgraded Yuanzheng-1A has far greater ability than the Yuanzheng-1, with an extended flight time of from 6.5 hours to 48, and its main engine can start nine times and can unload cargo seven times, compared with the older model that could carry one load and start its engine twice.

The Yuanzheng-2 has two engines and greater ability in orbit transfers.

"It now seems that the four Yuanzheng upper stage rockets can meet different mission needs and future designs will focus on improving them even more," Wang said in the CALVT report.

This systematic development of the upper stage of the rocket has helped with the versatility of the carrier rocket, making it suitable for mid-to-high orbits, Song commented.

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Sino-UK On-Orbit Assembly Telescope Project Kicks off
Nov 07, 2017

China and the United Kingdom recently kicked off a new project for the Future-Generation Space Telescope Research. The project was launched on October 24 in Changchun of northeast China.

The Ultra-Large Aperture On-Orbit Assembly Project is led by the Changchun Institute of Optics, Fine Mechanics and Physics (CIOMP) affiliated to the Chinese Academy of Sciences, and the University of Surrey (UoS), UK.

Space telescope on-orbit assembly technology is a completely new field. How to complete the telescope automation, intelligent assembly is faced with a series of technical problems. CIOMP, in cooperation with the UoS, will develop the main key technologies needed for on-orbit assembly of space telescopes and jointly contribute to the promotion of human science and technology development.

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Idea figure of the Future-Generation Space Telescope (Image by CIOMP)

The project will develop a 10m level aperture on-orbit assembly space telescope for a range of space science applications, all of which involve complex cooperation in technical planning, conceptual design and review, and demonstrating key technologies and manufacturing proof-of-concept prototypes.

The research collaboration will also aim to establish international partnerships towards "On-orbit Assembly International Science Organization” (OAISO), to help promote and develop future international space missions for the underpinning technologies.

This research project has emerged from active exchanges between the two organizations in September 2016. An MOU was signed by the President and Vice Chancellor of UoS, Professor G Q Max Lu, and CIOMP President JIA Ping. Both parties agreed to explore a range of collaborative endeavors, including the initiation and launch of a joint laboratory.

The start of the CIOMP/UoS joint project will enhance the China/UK cooperation in astronomy and space technology. It is surely set to become a shining star.
 
Astronomical event inspires Chinese scientists to launch groundbreaking project

2017-11-08 09:36 Global Times Editor: Li Yan

Chinese scientists are working on the possible launch of a dedicated space telescope to study high energy light from gravitational waves, according to China's top observational astronomy researchers on Monday.

The decision came after scientists from around the world announced on October 16 that they had for the first time detected ripples in space, known as gravitational waves, together with light created by a spectacular collision of two neutron stars.

The detection of the gravitational wave signal was made at 8:41 p.m. on August 17 (Beijing time) by twin detectors of the Laser Interferometer Gravitational-wave Observatory (LIGO), located in Livingston, Louisiana, and Hanford, Washington.

About two seconds after the gravitational wave signal ended, a bright flash of light in the form of gamma rays was detected by US space agency NASA's Fermi space telescope, Xinhua News Agency reported.

In the hours, days and weeks that followed, other forms of light or electromagnetic radiation - including X-ray, ultraviolet, optical, infrared, and radio waves - were detected.

Originally predicted in the early 20th century by Albert Einstein, gravitational waves caused by cataclysmic cosmic events result in ripples that propagate through spacetime, just like the movement of waves away from a stone thrown into a pond.

First results

Chinese scientists also on October 16 announced their successful observation of the "optical counterpart" of gravitational waves coming from the merger of two binary neutron stars using a survey telescope in Antarctica.

The Chinese telescope independently observed optical signals resulting from the merger the next day, among some 70 telescopes on the ground or from space across the world, according to the Chinese Center for Antarctic Astronomy.

It was the first time humans have detected gravitational waves and the corresponding electromagnetic phenomena resulting from a binary neutron star merger.

The merging process ejected radioactive material more than 3,000 times the mass of the Earth at a speed of up to 30 percent the speed of light, said Wang Lifan, director of the center.

The collision of binary neutron stars is accompanied by a series of electromagnetic phenomena that are crucial to research in origins of heavy elements like platinum and gold.

The light-based detections that followed showed that the collision of the neutron stars released newly synthesized heavy elements into the surrounding universe.

That's "the first concrete proof that such smashups are the birthplace of half of the universe's elements heavier than iron, including gold and platinum," the LIGO team said in a statement.

When these two neutron stars collided, there were only four X-ray and Gamma-ray telescopes across the world facing the area where this historical astronomical event was taking place, and China's first Hard X-ray Modulation Telescope (HXMT), better known as "Huiyan" (Insight), was among them, the China Science Daily reported on Monday.

Huiyan space telescope is under the commissioning operation by the astronomers at the Institute of High Energy Physics (IHEP) of the Chinese Academy of Sciences (CAS).

Huiyan was one of the first of 70 telescopes to report their observation of the merger, and their findings were included in the discovery paper of this gravitational wave event together with other telescopes from around the world, including LIGO in the US and the Virgo in Europe.

New inspiration

Xiong Shaolin, the head of the IHEP research team on gravitational waves, said that inspired by the ground-breaking detection of the light from the merger event, scientists at IHEP are working round the clock to set up a project to launch a special X-Ray and Gamma-Ray telescope, hopefully by 2020, for the future study of high energy light emitted by gravitational waves.

Compared to Huiyan, which is primarily designed for detecting black holes in our galaxy, the new space satellite will focus on the study of gravitational waves, and will be much smaller in size and much cheaper, Xiong added.

Furthermore, the chief engineer (Liu Cong-Zhan) of the Huiyan space satellite was quoted by the China Science Daily as saying that "IHEP has also launched a ground-based telescope to conduct study on a specific polarization mode of the cosmic microwave background (CMB) radiation in Ngari, southwest China's Tibet Autonomous Region.

It is the first of its kind in the northern hemisphere and at the world's highest altitude."

CMB is thought to be leftover radiation from the Big Bang, or the event that resulted in the creation of the universe.

Liu said that the special properties of CMB radiation had never been detected, and if Chinese scientists could achieve this, it would be of great significance for mankind's understanding of the birth of the Universe.

http://www.ecns.cn/2017/11-08/280061.shtml
 
China's future satellite navigation will be millimeter-accurate

The Beidou 3 will guide military munitions and drones.

By Jeffrey Lin November 7, 2017

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BEIDOU LAUNCH
The Beidou satellite is usually launched by LM-3 space launch vehicles.
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China's military is updating its satellite navigation system, launching tech that'll offer super accurate guidance for munitions and drones.

On Sept. 29, China launched two Beidou 3 satellites from a Long March 3C rocket from the Xichang Satellite Launch Center in Sichuan province. Another two Beidou 3 satellites will launch before the end of 2017, part of a network of 20 Beidou 3 and 10 older Beidou 2 satellites set to go up by 2020.

Civilian GPS receivers generally achieve higher accuracy by combining signals of several satellites, and indeed the completed Beidou Navigation Satellite System is expected to provide global coverage, with millimeter-level accuracy.

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BEIDOU 3
Beidou 3 satellites will offer superior accuracy compared to current Chinese navigation satellites.
China Academy of Sciences

Plus, thanks to a new, more accurate atomic clock, the Beidou 3 satellites will also be able to send more precisely timed radio pulses. Atomic clocks, which are set to the oscillations of atoms from stable isotopes, are highly accurate. The American NIST-F2 atomic clock, for example, is designed to lose only a second every 300 million years.

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The Beidou 2/Compass navigation satellites will have 35 satellites once completed, with 5 in geosynchronous orbit, and 30 in middle earth orbit.
China Academy of Space Technology, via Escobar on Sinodefence Forum

The system will also likely have new, jam-proof chips. Allystar Technology has unveiled a computer chip for use in Beidou receivers, providing instant accuracy without the aid of augmentation by ground control stations. This computer chip's ability to enhance satellite navigation signals could enable military Beidou users to withstand enemy attempts to jam satellite navigation.

The Beidou 3 satellite navigation service is expected to be available only to Chinese military and national security users for the foreseeable future. The updates could be particularly useful for Chinese unmanned systems (like small quadcopter drones) as well as long-range cruise missiles.

https://www.popsci.com/china-beidou-3-satellite-navigation-system
 
China launches new meteorological satellite
Source: Xinhua| 2017-11-15 04:08:18|Editor: Zhou Xin



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China launches a new meteorological satellite, Fengyun-3D, at 2:35 a.m. Beijing Time from the Taiyuan Satellite Launch Center in northern China's Shanxi Province, Nov. 15, 2017. A Long March-4C rocket carried the satellite into space. The satellite has entered its orbit. (Xinhua/Zhang Hongwei)

TAIYUAN, Nov. 15 (Xinhua) -- China launched a new meteorological satellite, Fengyun-3D, at 2:35 a.m. Beijing Time Wednesday from the Taiyuan Satellite Launch Center in northern China's Shanxi Province.

A Long March-4C rocket carried the satellite into space. The satellite has entered its orbit.

Fengyun-3D is one of China's second generation of Polar-Orbiting Meteorological Satellites, which can provide global three dimensional all-weather and multi-spectral remote sensing images.

The satellite will form a network with the Fengyun-3C satellite, which was launched into space in September 2013, to improve the accuracy of atmospheric sounding and enhance the monitoring of greenhouse gases. The network will help China's disaster relief work.

The Fengyun-3D satellite and the Long March-4C rocket were developed by Shanghai Academy of Spaceflight Technology under China Aerospace Science and Technology Corporation.

The launch was the 254th mission of the Long March rocket series.

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China launches new weather satellite Fengyun-3D to provide better free data
  • By Gong Zhe
  • 2017-11-15 08:39 GMT+8
  • Updated 2017-11-15 15:01 GMT+8

China launched a new meteorological satellite, Fengyun-3D, at 2:35 a.m. Beijing Time Wednesday from Taiyuan Satellite Launch Center in northern China's Shanxi Province.

Fengyun-3D is one of China's second generation of Polar-Orbiting Meteorological Satellites, which can provide global three dimensional all-weather and multi-spectral remote sensing images.

The satellite will form a network with the Fengyun-3C satellite, which was launched into space in September 2013, to improve the accuracy of atmospheric sounding and enhance the monitoring of greenhouse gases. The network will help China's disaster relief work.

New instruments

Chief manager of the Fengyun-3 system Zhang Peng told thepaper.cn that the D satellite was designed to run for five years, with 10 advanced remote sensing devices.

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Zhang Peng talks with CCTV reporter. /Screenshot from CCTV

One of the main functioning parts is a spectral imager, the first of its kind to sample the Earth at a resolution of 250 meters per dot, as reported by thepaper.cn

In addition to actual color images, it can also monitor the clouds and water vapor to help China research its environment.

Zhang also introduced the greenhouse gas monitor on the satellite, which can get the amount of carbon dioxide, carbon monoxide and methane on a global scale.

The data is already being used at the on-going COP23 to for analysis.

"We have also introduced two more ground stations, one in China's Kashi, the other in the Antarctica," Zhang told CCTV.

Data for free

The administration of the Fengyun system promised last month to share the collected data with the world for free.

And they are doing it, as the data can already be downloaded at satellite.nsmc.org.cn, the system's official data portal.

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The English version of the data portal /Screenshot from satellite.nsmc.org.cn

The system has collected more than 3,600 TB of data since 2005, as shown on the website.

Fengyun-3D's data was not available until noon Beijing Time.

But the data should be available soon since China Meteorological Administration revealed on Wednesday that Fengyun-3D could send back 90 percent of its data in 80 minutes.

 
Land Cover Atlas Sheds Light on 20-Year Environment Change of China
Nov 16, 2017

Land cover, as a geographical feature, is a synthesis of observable natural and artificial objects on the surface of the Earth. The dynamics of land cover change on the planet is a record of how mankind interacts with the Nature and their arduous efforts to improve living conditions since the primitive age of "slash and burn”.

At the country level, land cover changes over time can be regarded as indicators that shed light on its natural environment, ecosystem, economic development, and the livelihood of the people on this land.

The world's first land cover atlas “Land Cover Atlas of the People’s Republic of China (1:1,000,000)” has been published in September, 2017 in both Chinese and English. This atlas is designed according to international map sub-division standard. That atlas provides the most comprehensive look at land-surface conditions across China, and records its land cover changes in 1990, 2000, and 2010, a period witnessing rapid economic growth of China.

The land cover data (ChinaCover) used in this atlas has the following unique characteristics:

The classification system with six primary classes and 40 secondary classes was established, which conformed both to international classification criteria and the land cover features of China, and assured comparability and convertibility to other commonly used classification systems.

Chinese environmental satellite data (HJ-1A/B) was used for the land cover mapping for the year 2010, supplemented with synthetic aperture radar (SAR) data to improve recognition of water body and built-up surfaces.

A total of 111,356 ground samples were used for establishing the classification training sample dataset, creating classification criteria, controlling quality and revising misclassified pixels.

The automatic pre-processing of huge amount of remote sensing data was accomplished using a high performance computing platform. An object-oriented based classification method was employed to produce the ChinaCover2010. A change detection algorithm was used to generate the ChinaCover2000 and ChinaCover1990, thus ensuring data comparability over the three time periods.

A quality control specification (QCS) system was established for data processing, segmentation, classification and mosaicking. Validation was carried out for ChinaCover2010 using 31,658 independent ground-surveyed samples, which showed an average accuracy of 94% for the primary classes and 86% for the secondary classes.

The atlas is produced to meet a wide variety of national spatial needs for the agriculture, forestry, water conservation and environment protection. It provides access to the application of these land cover data, which can be used to study a wide range of fields such as global change, biodiversity conservation, and to assess the rates, trends, causes and consequences of contemporary China’s land cover change.

The land cover types such as forest lands, grasslands, and wetlands are important participants in the process of carbons cycle. Therefore, related data offered by the atlas also provides important reference for Chinese government to make carbon-budget policy by assessing the capacity of carbon sequestration based on the land covers, and therefore facilitate China to achieving its carbon-dioxide emission goals on the Paris Climate Change meeting.

It takes six years to complete the work from the data production in 2011 to the atlas publication in 2017. The atlas compilation, which is led by the Institute of Remote Sensing and Digital Earth (RADI) under the Chinese Academy of Sciences (CAS), involves collaborative efforts of over 240 scientists and technicians from CAS institutes, other research, education and government agencies.

This work is mainly supported by CAS Strategic Priority Research Program “Climate Change: Carbon Budget and Relevant Issues” and the Ministry of Environment Protection (MOST) / CAS joint project on “Monitoring and Assessment of National Ecosystem Changes between 2000 and 2010”.



Land Cover Atlas Sheds Light on 20-Year Environment Change of China---Chinese Academy of Sciences
 
Upgraded Prototype of HERD Calorimeter Completes Beam Tests
Nov 15, 2017

A beam test of an upgraded calorimeter prototype of the High Energy cosmic Radiation Detection (HERD) facility was conducted at the CERN SPS H2 and H4 beam lines from Oct 2, 2017, to Nov 1, 2017.

HERD, a China-led mission with a large international collaboration, is a flagship scientific experiment for China's future Space Station. The main scientific objectives of HERD are indirect dark matter searches with unprecedented sensitivity, precise cosmic ray spectrum and composition measurements up to the knee energy, and gamma-ray monitoring and surveys.

The calorimeter prototype consists of 250 LYSO crystals, and is an upgraded version of a 2015 prototype, with a more advanced camera and a new technique of crystal encapsulation. During the beam tests, data on protons, electrons, muons and fragmented ions were collected, to test the performance of the prototype in key areas including energy linearity, energy resolution, particle ID power, off-axis capability and charge discrimination capability.

Preliminary results showed that the non-uniformity of the crystals is well controlled, around 2:1, which is much better than the previous prototype. The energy resolution is better than 1.3% for 200 GeV/c electrons, and fragmented ions with Z>20 are clearly seen in the spectrum of fragments.

All expected design criteria were achieved in this test. The novel design of a 3D calorimeter with WLS fiber + IsCMOS/ICCD readout is proved to be feasible for broad-band observation with high energy resolution.

Around 30 scientists, from the Institute of High Energy Physics (China), Xi’an Institute of Optics and Precision Mechanics (China), Guangxi University (China), Beijing Hamamatsu (China), the University of Geneva (Switzerland), INFN Perugia (Italy), INFN Bari (Italy) and INFN Lecce (Italy), participated in the beam test.

In between the proton beam test and ion beam test, the 5th HERD international workshop was held at CERN. Progress on R&D for the instruments, MC simulation, beam tests underway, and future activities were discussed in depth.

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Figure: Left: HERD calorimeter prototype (China) and the trigger and tracking system (Italy & Switzerland) installed on the SPS H2 line. Right: Reconstructed spectrum of 200 GeV/c electron. (Image by IHEP)


Upgraded Prototype of HERD Calorimeter Completes Beam Tests---Chinese Academy of Sciences
 
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