Category China in Space

From the opening of its space program in 1956, China established the full range of infrastructure necessary for a comprehensive space program. This comprised:

• a rocket engine testing station;

• static test hall;

• vibration test tower;

• wind tunnels;

• leak detectors;

• radio test facility;

• vacuum chamber.

One of the first was the Beijing Rocket Engine Testing station (1958), also called the Fengzhou Test Centre, now the Beijing Institute of Test Technology and formally part of CALT, 35 km from Beijing. The first set of four rocket test stands was completed in 1964 under the direction of Wang Zhiren and she designed them to run up to four engines at a time and simulate ground-level and high-altitude tests. A

Engine testing center, south-west of Beijing (Peiping), from declassified CIA files.

Rocket engine testing. Stands were built into the side of a mountain.

large stand was completed in 1969, 59 m high, with a cooling system drawing on a tank holding 3,000 tonnes of water cooling the engines with 35,370 nozzles. Subsequent stands were built for horizontal engine tests. Like Jiuquan cosmodrome, the engine testing station was quickly spotted by overflying American reconnais­sance aircraft and satellites. The ideal site for a testing station was a ravine, so that the stand could be built on the hillside and the flames deflected down into the ravine along a concrete outflow.

CALT’s static test hall was, when built in 1963, the largest building in China, taking eight months to construct and involving the driving of 1,300 piles – some as long as 10 m – and two pourings of more than 5,000 m3 of seamless concrete. Entire rockets can be tested there at a time. For the development of the communications satellite, a large vertical dynamic equilibrium machine was developed. Construction of the machine began in 1976 and it was operational five years later. Also constructed that year was a 50-m-tall vibration test tower. On the outside, it looked like an unprepossessing, shabby yellow-and-orange brick grain mill, but it was able to test all the likely stresses an ascending rocket was likely to experience. With 13 floors and 11 working levels, entire rockets were hoisted into place on the stand, gripped by bearing rails on the floors, and then shaken to exhaustion by 20-tonne hydraulic vibration platforms.

A series of vacuum chambers was built in Beijing and Shanghai in the 1960s, able to simulate up to 10-7 torr (1 torr = 1/760 atmospheres) and later, in the case of geostationary satellites, 10-13 torr. They are located at the Environmental Simulation Engineering Test Station in Beijing and the Huayin Machinery Plant in Shanghai. Here, spacecraft are lowered by crane to be alternately frozen, heated, shaken, and baked in a vacuum. Supercooled helium is the chief agent for freezing the chamber while pumps are used to suck the air out. The test station in Beijing has six chambers, called KM, the largest being 12 m in diameter and 22 m tall. The most recent is the 12-m-diameter KM6 (1998), designed to test the Shenzhou spacecraft. To test against leakages in satellites, the Beijing Satellite General Assembly Plant developed a highly sensitive leakage detector using krypton-85, able to pick up a leakage of 50 microns (half the width of a human hair). For the Long March 3 third stage, the Lanzhou Physics Institute developed a helium mass spectrum leakage detector. To test satellite radio systems, a test hall was built whose primary feature was that it has no metallic components, so it is made entirely of glued red pinewood.

More recently, testing facilities were built for spacecraft and the testing of robotics at Harbin Polytechnical University (2000). Called the Environmental and Engineer­ing Space Laboratory, it is designed to simulate the vacuum and radiation of the space environment, from elements to materials and full-scale spacecraft. For Shenzhou, CAST has a 100,000-class clean room, an anechoic chamber built with the help of European Aeronautic Defence and Space (EADS) Astrium, and a thermal vacuum chamber 24 m tall and 12 m in diameter. There is a Shenzhou simulator and a 10-m-deep hydrotank. China’s first wind tunnels were built in 1959 for the Aerodynamics Research Institute, Beijing, and were first used to determine the air flow and pressure on rockets climbing and staging, and more recently for testing airflow around shuttle-type spacecraft.

Chapter 4 tells the story of the Chinese Fanhui Shi Weixing (FSW) recoverable satellite series. This began in 1975 and, since then, China has carried out 23 recoverable missions, including one recently in the Shi Jian series, called “the seeds satellite”. These satellites have been important for testing new technologies, Earth observations, and biology.

PROJECT 911

China was the third country to recover a satellite from orbit. The idea of a recoverable Earth satellite in China went back to 1964 and the work of engineers in the Shanghai design team. They had been inspired by what they read of the American Discoverer series of recoverable satellites in the early 1960s. The concept was first formally proposed in the Chinese Academy of Sciences’ Proposal on Plan and Program of Development Work of Our Artificial Satellites, approved in August 1965, and hardened up during a design conference in March 1966. The Shanghai bureau was awarded the task and it was named project 911.

Design studies began immediately and were settled in the course of a three-day conference in September 1967. It was agreed to build a satellite with a weight of 1,800 kg (payload was 150 kg) and a typical orbit of 173-493 km, 91 min, 59.5°. It was given the name in Chinese Fanhui Shi Weixing, or “recoverable experimental satellite”. Apart from verifying the ability to recover satelhtes from orbit, the precise purpose of the program has never been entirely clear. The American Discoverer, although promoted as a research program, was actually a military photo­reconnaissance program designed to photograph Soviet military facilities and the Chinese later announced that the FSWs carried out Earth observation work, its cameras having a resolution of 10 m and a length of 2,000 m of film [1]. At the same time, another purpose of the FSW was probably to pave the way for an early manned flight (see Chapter 8). Whatever its original purpose, later versions of the FSW were also used to conduct a range of microgravity experiments in orbit. Whether this was because of an improvement in the international climate, or the Umited military reconnaissance value achieved from the FSW missions, or a form of

B. Harvey, China in Space: The Great Leap Forward, Springer Praxis Books,

DOI 10.1007/978-l-4614-5043-6_4, © Springer Science+Business Media New York 2013

diversification is a matter of guesswork. The military intelligence benefit from orbiting a recoverable cabin collecting 10-m-resolution images for a week every year is probably quite limited. Ultimately, the lasting achievements of the program were in civilian applications.

The use of photography for military reconnaissance was developed in the 1960s by both the Americans (Discoverer) and the Russians {Zenit, Yantar). Both had flown high-quality film, which was then returned to the Earth in a descent cabin for developing and interpretation, also called wet-film technology. The principal drawback of the system was that no data could be examined until the cabin returned, which reduced its value in following a rapidly evolving military situation. From the 1970s, the Americans moved to digital imaging, with photographs relayed electronically from orbit, but the Russians persisted with high-quality film – recoverable technology right into the 2010s {Kobalt). Eventually, the Chinese would move to digital technology (Zi Yuan and Yaogan).

The task of developing the project fell to the China Academy for Space Technology (CAST), while a new rocket, the Long March 2, was developed by the China Academy for Launcher Technology (CALT). Just as the civil version of the Dong Feng 4 missile had been the Long March 1, so in this case was the Long March 2 related to the Dong Feng 5. Progress was held up by the later phases of the cultural revolution but for which the first launch might have appeared several years earher than it eventually did. Recovering satellites posed difficult engineering challenges: devising a protective heat shield to ensure the capsule survives re-entry temperatures of 1,200°C, the development of retro rockets, a very precise attitude control system, quality ground tracking to prepare the cabin for the precise moment of re-entry, and search-and-recovery systems. These engineering challenges required the development of ever more sophisticated ground-testing equipment. A thermal vacuum chamber called the KM3 was constructed by the Institute of Environment Test Engineering and the Lanzhou Institute of Physics, achieving a vacuum level of КГ9 torr. The Xian Satellite Surveying and Control Centre was built so as to follow the satellite in orbit.

The Chinese had no previous experience of making heat shields. They did not wish to use ablative heat shields of the type developed by the US and Soviet Union in the 1960s, in which the material progressively burned off during the descent, enough remaining for the cabin to survive, but they were very heavy. Equally, they knew they did not have the capacity to go straight to light, low-density foam-type shielding of the type subsequently used by the American and Soviet shuttles (tiling). They eventually found a non-ablative material whose qualities lay somewhere in between – a carbon composite material called XF, able to withstand re-entry temperatures of 2,000°C. Contrary to some Western reports, the shields were not made of wooden oak planks (Europe’s Atmospheric Reentry Demonstrator (ARD) did use resin processed from Cork oak).

The recoverable series required a relatively advanced level of automation: a new three-axis attitude control system using an infrared horizon scanner and a gyrocompass, with analog computers, Sun and Earth orientation sensors, an inertial measurement unit, and a cold gas thruster system to orient the spacecraft. A camera

system was developed by the Changchun Institute of Optics and Fine Systems, comprising cameras for ground photography and side-pointing cameras for stellar photography (so as to work out the precise position of the spacecraft in orbit). To come out of orbit, a solid-fuel rocket was developed. The parachute system proved problematical and four air-dropped cabins were lost in tests when the parachute failed to open.

The FSW satellites were a quantum leap in size and scale beyond the first two satellites. Coming in at just under 2 tonnes, the cabin itself was beehive-shaped, 3.1 m tall, and ranging from 1.4 m in diameter at the forward end to 2.25 m in diameter at the large end. The satellites comprised a blunt cone capsule placed on a service module. During the mission, the nose was pointed in the direction of travel. At the end of its mission, when it reached Chinese territory, the spacecraft was swiveled through 100°, pointed nose down directly toward the Earth, and the sohd retro-rocket was fired, to descend almost vertically from orbit. This was a crude means of returning to the Earth – one that used up a substantial amount of fuel, but had the advantage of ensuring that retro-fire could be commanded over China and recovery would take place in China (by contrast, Russian spacecraft made a gentler descent, but with retro-fire commanded far away over the South Atlantic). On the other hand, such a retro-fire maneuver required a big velocity change of 650 m/sec, much more than the standard Russian or American re-entry profiles (about 175 m/ sec), while the angle of retro-fire must be very accurate, for each degree out meant a 300-km difference in the landing spot. At 16 km, the FSW dropped its heat shield and retrorockets, a parachute opened, and the cabin came down at 14 m/sec in Sichuan province in southern China. The Chinese landing technique, guaranteeing

landing in China, was important if sensitive film were on board (the Russians fitted self-destruct devices to their spacecraft to stop theirs falling into unfriendly hands). To help rescuers find it, the cabin was equipped with a transponder and two location beacons.

Sichuan province in the south-west of the country was chosen as the recovery zone, although it is hilly and often subject to thick clouds and mists. Photographs from the recovery area have frequently shown Mil-type recovery helicopters hovering against a background of mountains, follow­ing the descent craft down, and then lifting it away for post-flight exam­ination. The scene is one of the space cabin lying on the hillside, its red – and-white parachute streamed out alongside, the recovery teams safing and checking the cabin, and rural workers gathering on the nearby hills to watch the excitement.

The chief designer of the rocket to carry the FSW, the Long March 2, was Tu Shoue and the rocket remains in service 40 years later (see Chapter 3). Made of high – strength aluminum copper alloy, it was the first Chinese launcher to use full computer guidance and gimbaled engines. Its lightweight medium-speed, small – capacity digital computer was the first of its kind in China. A particular feature of the ascent was interstage glide: once the second-stage engine had completed its burn, the maneuvering vernier engines would continue to fire as a main engine, which enabled an extra 500 kg of payload to be carried.

Chief designer of the FSW cabin was Wang Xiji, born in 1921 in Dali, Yunnan, a graduate of Xian University who went on to Virginia Institute of Technology, where he was awarded a doctorate in 1949, returning to China the following year and becoming director of the Shanghai Institute of Mechanical Engineering and Design in 1958.

The Cox report had the desired effect of keeping China out of the world launcher market for seven years – and, conversely, denied China foreign earnings that might have funded other parts of its space program. In response, China eventually managed to break the ITAR blockade with Western customers and then searched further afield for new customers who also might legitimately evade American export

controls. Its instrument was a new, much more advanced domestic communications satellite, the Dong Fang Hong 4, able to work in the new internet, high-speed data transmission and Direct Broadcasting to Home (DBH) markets. This was such a big project that it featured in the five-year plan, being approved by the government in 2001. The Dong Fang Hong 4 series was much heavier (5.1 tonnes), enabling it to carry between 22 and 52 transponders (in minimum configuration, 18 transponders at 36 MHz and four at 54 MHz) with high-capacity data links. To do this, it had solar wings a record 32 m across with an area of 62 m2, wider than some sporting fields, able to generate between 10.5 and 13 kW of electrical power. Its precision pointing was 0.06° in pitch and 0.2° in yaw, able to reach 45-cm dishes, with an operating period of up to 15 years.

China’s intention was that the satellite be designed, assembled, and tested in China, but with European countries contributing key components, so as to match the highest worldwide standards. Four companies submitted proposals, the winners being France’s leading telecommunications company, Thales Alenia. The aim of DFH-4 was to double the capacity of the DFH-3 and at least match the Western capacity of the Spacebus 3000 and Boeing 702. Dong Fang Hong 4 took five years to develop and the first DFH-4 was launched by the CZ-3B on 28th October 2006. This was Sinosat 2 (Xinnuo 2) for the Sinosat company, whose 22 transponders were to be located at 92.2°E, just west of Sumatra, to provide TV and broadband to small dishes in China and Taiwan.

Although designed for 15 years, the Chinese were deeply shocked to find that it failed in less than 15 hr. There was an electrical short circuit and the solar panels did not open. For 10 days, they used the limited communications with the spacecraft to struggle to open them. They finally gave up on 8th December. Sinosat 2 was allowed to drift off station to 70°E. In March 2008, the Chinese made another attempt at resuscitation, but it continued to drift, reaching 115°E by January 2009. It was finally decommissioned and taken out of orbit that July.

The failure of the DFH-4 on its first mission attracted considerable Western attention in media which normally ignored Chinese launchings, even their manned ones. The Aviation Week & Space Technology accurately described it as “the worst spacecraft failure in the history of the Chinese space program and a major setback” – but that was in a program in which on-orbit failures were rare. Investigators concluded that, although solar panels rely on individual hinges and it is not unknown for individual hinges to fail, a total deployment loss was unusual and most likely caused by a massive electrical or computer failure at that point or even earlier. The cost to China was estimated at between €150m and €400m – but would have been even more catastrophic if the first launch had been for a foreign customer. The setback, whilst unwelcome and attracting much adverse foreign news coverage, had only limited implications for other parts of the Chinese space program. It forced China to rely on other satellites for the upcoming Olympic Games. The original mission was quickly replaced by Sinosat 3 (Xinnuo 3, also called Zhongxing 5C), 125°E, on 31st May 2007, but this was an older DFH-3, a stop-gap while the DFH-4 was redesigned. After this was done, Sinosat 3 was relocated to 3°E, where it was leased by Eutelsat and renamed Eutelsat ЗА [4].

Despite the domestic failure, China still went out to win foreign DFH-4 contracts with Nigeria, Venezuela, and Pakistan. China offered not only to sell comsats to developing nations, but also to provide delivery to orbit and the loans to finance the whole enterprise. The first export was for Nigeria, where China had outbid 21 rivals in a competition, the Nigerians paying €250m. The satellite was to be positioned over 42°E and, for 15 years, bring communications to villages, broadcast television, and provide phone services, using 14 Ku-band transponders for southern and western Africa, C-band for central and southern Africa, and an L-band for navigation users. Not only did China build the satellite, but it also provided the loan to finance it and the training to operate it from Abuja tracking station.

Nigerian government officials, including President Olusegun Obasanjo, attended the televised night-time launch on 13th May 2007 in Xi Chang. The arrival of

Nigcomsat made Nigeria the leading African space communications user and promised a revenue of €50m a year. Disappointingly, it failed on 10th November 2008 when its solar power broke down after only 18 months. The following March, China agreed to replace it at its own expense (this apparently had been a condition of the contract). The replacement DFH-4 was duly launched on 19th December 2011, arrived on station a week later, completed its on-orbit tests in the first two months of the new year, and was formally handed over to Nigeria at a ceremony at the Obasanjo Space Centre in Abuja on 19th March 2012.

The second export was Venezsat, subsequently named the “Simon Bolivar”, launched on CZ-3B on 29th October 2008 for Venezuela, watched in Xi Chang by the country’s president, Hugo Chavez. Venezuela paid €200m for the satellite in 2005 after considering offers from Russia, Europe, and India. The Venezuelans required 14 transponders in the C-band and 14 in the Ku-band operating from 78°W, with coverage not only of the Americas, but also extending to Iberia. The builders were the Beijing Siangyu Space Technology Corporation, with special assistance from Thales Alenia for the power supply for €3.2m. A contract was subsequently agreed between China and Venezuela in April 2011 for an Earth and climate observation satellite (this may be called VRSS-1). A third successful export, Paksat 1R for Pakistan, reached orbit in August 2011 and was declared operational that November.

The success of the Venezuelan mission and the ultimate success of Nigcomsat encouraged other countries. In April 2010, Bolivia became the next to sign up for a DFH-4 comsat, called the Tupac Katari (named after the eighteenth-century leader
of resistance to Spain), designed to provide television and communications channels for literacy, education, health care, and social services as well as profit-making commercial services, with launch set for 2014. Financing came as €30m from the Bolivian government and €200m from the China Development Bank. The package included two years’ training in satellite operations for 74 engineers in China for 2012-14. Further orders then came in from Laos, Indonesia, and Sri Lanka. China’s prices definitely undercut both Western and Russian prices: €20m for the CZ-2, €40m for the CZ-3A, €50m for the CZ-3C, €60m for the CZ-3B, and €40m for the CZ-4. Overall, China’s penetration of the world communications satellite launcher market was small, less than 10%, for Russia and Europe had an effective duopoly, but could well grow in the years ahead.

China broke into the international satellite market through a combination of self­interest, diplomacy, and business. Developing countries were interested to get satellites up, both for practical gains and as status symbols. Nigeria was the test case. Nigeria expected to pay off the satellite in seven years by leasing commercial bandwidth for television and banking services, while at the same time using it for social purposes, such as distance learning in remote rural areas, and for public service purposes, such as onhne access to government services and records and the remote monitoring of oil pipelines. Many Western companies avoided the competition for Nigcomsat because of their concerns about corruption, but China was undeterred and brought an accompanying financial package. The risks were outweighed by additional gains, such as oil deals, political connections, influence in Africa, and hard currency [5]. China is reported to be in negotiation for further launches for Belarus, Turkmenistan with Monaco, Columbia, and Congo, in each case using the CZ-3B, with discussions on Western or DFH-4 satellites.

After success abroad with the Dong Fang Hong 4, China started to deploy the satellite domestically. The first was Sinosat 6 (also cited as Xinnuo 6, Chinasat 6, and Zhongxing 6A), launched on 4th September 2010 on a CZ-3B from Xi Chang, a direct TV satellite located at 124°E and replacing the DFH-3 Sinosat 2. There was an unconfirmed report that it suffered a helium leak likely to reduce operational life from 15 years to 11.

The second domestic DFH-4 success was Sinosat 5 (also known as Xinnuo 5 or Zhongxing 10), launched on CZ-3B on 20th June 2011. All went smoothly, except that debris fell on a house downrange, causing a hole in the roof but thankfully no injuries. Its main function was to provide Direct Broadcast to Home services in Asia from 103.5°E and replace Zhongxing 5B but, in August, it moved to 110.5°E beside 5B. Table 5.6 lists the launches of the Dong Fang Hong 4 series.

Even as the DFH-4 was getting into service, China was planning its successor, the Dong Fang Hong 5. The DFH-5 is to weigh up to 7 tonnes, generate up to 20 kW of electricity, and will be launched by the CZ-5 heavy rocket. This is intended to break into the high end of the comsat market of high-data Ku-band transmission hitherto dominated by Loral, Boeing, Thales Alenia, and Astrium.

CONCLUSIONS: PROGRESS AND POLITICS

The communications satellite program was an important aspect of the moderniza­tion of China, bringing television, radio, telephone, banking, internet, newspapers, and educational programming to viewers, listeners, commerce, students, readers, and farmers in both dense urban and scattered rural communities. Communications satellites were a classic use of “leapfrog” technology, avoiding television masts and

phone lines to go straight to the ubiquitous satellite dish. The modernization of China by satellite communications was very much the achievement of the overall technical director of the program, Sun Jiadong, born in 1929, a graduate of the Zhukovsky Institute of Air Force Engineering in Moscow and involved in the space and missile program from the 1950s. The satellites developed an ever-longer lifetime, from three years (DFH-2) to six years (DFH-2A) to eight years (DFH-3). Despite some spectacular failures reducing the average, most actually worked for longer than advertised.

Way back in the 1970s, the development of communications satellites, involving the mastery of hydrogen fuels, the 24-hr orbit, and demanding performance by satellites themselves, was a formidable technical challenge. Since then, China caught up with and matched the performance of American and European communications satellites, selectively bringing in European expertise to do so.

Little can the Chinese have imagined that they would be confronted by such international political obstacles in attempting to develop their communications satellite program. The events that followed make for an extraordinary study of

intrigue, political lobbying, espionage, and partisan politics. The Chinese showed forbearance, persistence, and both technical and political resourcefulness in the face of the ever-tighter blockades set down by the Congress from the mid-1990s. After several years, they were rewarded by eventually breaking the stranglehold of ITAR so as to launch Western-built satellites and with satellite contracts with developing countries so as to launch the home-built Dong Fang Hong 4. As developing countries expand their telecommunications capabilities, this market can only be predicted to grow.

After a long gap, the Shi Jian series resumed on 8th September 2004, the new set bearing no resemblance to its predecessors. No scientific results were announced from the new Shi Jian missions, leading to Western speculation that they were primarily military in purpose, but they are treated here for convenience. Shi Jian 6 was a double mission, named Shi Jian 6A and 6B, launched on the CZ-4B from Taiyuan. It appeared that the double mission comprised quite different spacecraft, 6A being the 375-kg small CAST968 bus, while 6B was the much larger 975-kg Feng Yun satellite (note that some commentaries reverse “A” and “B”). The China Academy of Space Technology (CAST) has showed an image of one of the Shi Jians as similar in shape to its CAST968.

The initial orbits of both spacecraft were 96.6 min, 91.1°, and altitude 593­604 km. After a while, the smaller 6A began to make small maneuvers to enable flying in formation with the larger 6B, reducing its orbital period by 20 km and then lifting it back to 6B (e. g. on 7th and 14th October). Several Western analysts suggested that, because of the involvement of the China Electronics Technology Corporation, these were electronic intelligence satellites. Another explanation, coming indirectly from China itself, is that the larger spacecraft carried a radar imaging system whose accuracy is enhanced by an accompanying satellite making altimetric measurements while flying in formation [3].

Shi Jian 7 was launched into Sun-synchronous orbit as a single satellite on 5th July 2005 on CZ-2D from the new double pad in Jiuquan. It made one small maneuver shortly on entering 97.6° orbit, raising its perigee from 547 km to 558 km and keeping the same apogee, at 570 km. Apart from declaring that it would work three years on a science mission, no details were given, apart from a picture showing that it was a CAST968 model.

Because it was essentially a Fanhui Shi Weixing (FSW) mission, the Shi Jian 8 “seeds satellite” mission was reviewed in Chapter 4. To add to the further confusion over designators, Shi Jian 8 was then followed by Shi Jian 6 and then two more Shi Jian 6 flights, also called by the Chinese “Shi Jian 6 group 2”. They were launched from Taiyuan on CZ-4B on 23rd October 2006, deployed at 11 min and 12 min, respectively, with a similar mission to study the space environment for two years. Two years later, they were joined by another, third set of Shi Jian 6, 6-3A and 6-3B, on a CZ-4B from Taiyuan, into polar orbits of 91.1°, 580-605 km. The fourth set, Shi Jian 6-4A and 4B, came on 6th October 2010 on the CZ-4B, the A in a 588­604 km orbit, the В in a lower, looser intercepting ellipse of 566-604 km, but not apparently maneuvering. The Shi Jian 6-1 group and the 6-2 group were in the same orbital plane. There was also symmetry to the launch pattern: September 2004, October 2006, October 2008, October 2010.

Next up was Shi Jian 11 on 12th November 2009 into a much higher orbit of 699­703 km, 98.3°, but this time on a CZ-2C from Jiuquan. This was numerically puzzling, for Shi Jian 9 and 10 had yet to fly (Shi Jian 10 is a successor to Shi Jian 8, while, that same year, it was explained at the Zhuhai air show that Shi Jian 9 was a new type of spacecraft to test electric propulsion). As for the Shi Jian 11 series, no clear purpose was explained. Some Western commentaries took the view that this series was for missile early warning, being equipped with infrared sensors accordingly – but other space superpowers have always put their early-warning systems in much higher orbits (out to 39,000 km in the case of Russia’s Oko system). Electronic intelligence is also possible, but the favored altitude of the Soviet system was also a higher orbit, at 850 km. In any case, Yaogan appeared to be serving such a purpose.

This was followed six months later on 15th June 2010 by Shi Jian 12 on a CZ-2D from Jiuquan. It was launched into an orbit typical in the series, 575-597 km, 96.3 min, 97.7°, but was the beginning of an unusual set of events in orbit. Five weeks later, on 12th August, it maneuvered close to Shi Jian 6-3A and, on 19th August, to within 200 m – China’s first on-orbit demonstration of an interception. There was even some evidence that Shi Jian 12 came even closer and glanced off Shi Jian 6-ЗА, thus giving it a slight nudge. A closer look at its path showed how a total of six maneuvers had been made to achieve the interception, mainly involving plane changes, then moving to 4 km below and then 7 km above Shi Jian 6-3A. The maneuver was repeated in October [4].

These maneuvers were not announced by the Chinese, nor were they denied. They were first published in Novosti Kosmonautiki, following space journalist Igor Lissov’s analysis of orbital data published by the American military. Western opinion was divided as to whether these interceptions were harmless tests of orbital rendezvous maneuvers, or a sinister development paving the way for the interception and destruction of hostile satellites. Suspicions about the latter, though, were fuelled by a report of the Small Satellite Research Institute of CAST of a ground test of a system of parasitic nano-satellites which would, at a time of tension, attach themselves unnoticed to enemy satellites following a surreptitious rendezvous maneuver. Being very small, they would be unnoticed until it was too late. Attached to their hosts, they would await the command to disable them, either by explosion or by electronic interference. Whether this fiendish plan was a paper study, a threat, or a real project is difficult to tell.

The events of mid-August were only the beginning. After the August interceptions, Shi Jian 12 held a steady distance while maintaining orbit at around the 600-km mark, the altitude at which all subsequent maneuvers took place. Then, on 16th November 2010, Shi Jian 12 maneuvered to approach a second satellite, Shi Jian 6-1 A, holding at 5 km away, but moving to 1 km away on 4th December. Shi Jian 12 then maneuvered on 6th December to approach a third satellite, Shi Jian 6- 4A, on 6th December 2010, keeping formation at 1 km until breaking away on 26th December. Shi Jian 12 departed on 12th January 2011 to follow its original target, Shi Jian 6-1 A, now 180° away. This was its last reported maneuver, but, nine months later on 23rd September 2011, the hitherto passive Shi Jian 6-3A raised its orbit to 609 km and could be observed holding distant formation with Shi Jian 12. In other words, Shi Jian 12 conducted rendezvous with a series of different satellite targets in sequence – an impressive demonstration of planning and maneuvering.

Just as had been the case before, the next Shi Jians came from an earlier series and, to confuse things even further, the next Shi Jian was Shi Jian 11-3, even though 11-2 had not been launched. Shi Jian 11-3 was launched into a 689-704 km, 98.1° orbit, similar to 11-1 but with a different orbital plane. It was quickly followed by Shi Jian 11-2, which in turn was followed by 11-4, though it failed to reach orbit. The role of these single spacecraft is unclear and they have not served as rendezvous targets.

The Chinese have said almost nothing about the Shi Jian 6, 11, or 12 satellites or acknowledged their maneuvers, and no scientific papers have been pubhshed about their activities, even though they were officially studying “radiation and the space environment”. Even if they were testing new technologies, these outcomes have not been published either. There are, though, some official sources which may shed light on these missions. China Space Science and Technology, the principal journal of spaceflight in China, published a series of articles in 2010-11 that could have been connected to these experiments, such as “Rotated Formation Flying for Tethered Micro-Satellites”, “Hovering Method at Any Selected Position over Space Target in Elliptical Orbit”, “Guidance for Dynamic Obstacle Avoidance of Autonomous Rendezvous and Docking with Non-Cooperative Target”, “Application of Relative Measurement for Three Satellites in Formation”, “Rendezvous Orbit Design and Control of the Target Spacecraft”, “Target Spacecraft Phasing Strategy in Orbital Rendezvous”, “A New Kinematic Method for Flying-Around Satellite Formation Design”, “Orbit Design for Approaching Multiple Spacecraft Repeatedly”, and “Beam Synchronization Strategy for Distributed SAR SatelUtes Formation”. Chinese scientific literature is abundant with papers on formation flying, some very complex [5]. These papers demonstrate a high level of interest in formation flying and interceptions, but tell us little as to their ultimate purpose, be that for manned rendezvous and docking (the upcoming Tiangong mission), Earth resources (the Americans use formation flying for Earth observations, called the А-train), or for more sinister purposes. According to one set of these authors, Fanghu Jiang et al., “formations offer greater flexibility and redundancy at lower costs”.

There was nothing new about satellite interceptions or formation flying, for the Soviet Union developed an interceptor system in the late 1960s and formation flying with small Czech satellites from the late 1970s. The pattern of double satelhte missions (Shi Jian 6 groups 1, 2, 3, 4) to serve as targets for an interceptor (Shi Jian 12) is something new in astronautics, while the purpose of the single Shi Jian 11 missions (1, 3, 2) remains obscure. Table 7.3 summarizes the series.

October 2007 saw China launch its first Moon probe, the Chang e, and, by the following year, three Asian powers had spacecraft circling the Moon in a mini-space race between China, India, and Japan. It was followed by a second orbiter, with an extensive program of lunar research in the pipeline, with missions to Mars to follow.

PROJECT 211

Like most of China’s space projects, the roots of the Chinese Moon program went back some way. The first paper studies dated to 1962, when the University of Nanjing presented a text about a simple probe able to hit the Moon, as Russia had done in 1959. President Carter presented China with 500 g of lunar rock in 1978 and this was carefully studied by Chinese scientists.

UnUke the manned program, there were no rumors of Chinese Moon probes in the 1970s or 1980s, but China cannot but have noticed how, in 1990, Japan broke the superpower monopoly on missions to the Moon when it sent the small probes Hiten and Hagoromo there. Consideration was given to launching a Moon probe in 1994 rather than a manned space program, but it was decided to give priority to the more ambitious manned program and delay the Moon probe for the time being [1]. The idea of a Moon probe would not go away, for, at a 1995 Chinese Academy of Sciences conference, the director of space research, Professor Jiang Jingshan, told journalists that a pre-study of a lunar satellite was under way following a proposal by one of its senior members, Min Gurong. In 1997, three designers obtained funding under project 863 to research a possible lunar program. Yang Yiachi, Wang Dayan, and Chen Fangyun pubhshed their results under the title of Recommenda­tions for the Development of China’s Lunar Exploration Program. The following year, an expert group was appointed, issuing a report entitled Overall Design and Key Technology Elements of a Lunar Exploratory Robot. This set three objectives for a Chinese Moon probe: improved knowledge of the formation of the lunar surface, its gorges, and craters; monitoring, from the lunar surface, the solar wind, radiation, and meteors; and analysis of lunar rocks with an on-board laboratory, to detect the presence of Helium 3.

B. Harvey, China in Space: The Great Leap Forward, Springer Praxis Books,

DOI 10.1007/978-l-4614-5043-6_9, © Springer Science+Business Media New York 2013

Symposia on lunar probes were held at Tsinghua University early in the new century. The Dean of the Department of Computer Science and Technology at Tsinghua University, Sun Zengqi, told the International Conference on Engineering and Technological Sciences 2000 that his department had explored a range of robotic technologies that could be used for lunar exploration – in collecting samples, exploring the lunar surface, deploying instruments, sending back television, and, ultimately, paving the way for manned landings. At the same time, Tsinghua University completed a study of the robotics involved in a lunar sample return mission modeled on that carried out by Russia’s Luna 16, 20, and 24 in 1970-76. An imported Japanese robot was rebuilt so that it could be manipulated, from the Earth, to grasp rocks to be lifted up and placed in a recovery capsule for return to the Earth. The following year, the university built a model miniature six-wheel solar – powered lunar rover, not unlike the Sojourner rover landed by the Americans on Mars. About a dozen institutes became involved in rover design in the early 2000s, such as the Shenyang Institute of Automation.

The lunar program was discussed at the China aerospace forum over 8th – 9th October 2001. The conference, entitled Policy and Perspectives on China Aerospace Development, was told by Xu Dazhe of the Chinese National Space Administration (CNSA) that China was capable of a lunar mission. The following month, on the anniversary of the government white paper on space exploration (see Chapter 10), Liang Sili of the China Academy of Sciences and Sun Laiyan, vice­director of the CNSA, gave 2005 as the target date for the first Chinese unmanned mission to the Moon. In January 2002, the China Space Journal outlined the three prospective lunar missions: an orbiter, soft-lander, and sample return mission. Writers argued that China could start its lunar program with relatively sophisticated probes: there was no need to repeat the type of basic missions flown by the United States and Soviet Union in the early years of the Moon race. In May 2002, chemistry expert and director of the Beijing national observatory Ouyang Ziyuan was appointed chief scientist for China’s Moon exploration project. The cooperation program with Russia was extended to add missions to the Moon, Mars, and further afield. By the following year, no fewer than 67 papers had been put into the public domain about how China might carry out a lunar mission.

Approval for a Chinese lunar mission was finally given at a meeting of the government on 28th February 2003 and given the title project 211 (apparently, the first space project approved in the twenty-first century). It was given a popular title, the Chang e program (pronounced in EngUsh “chung-ur”), called after a beautiful fairy who took a magic potion, flew to the Moon, and became a celestial goddess. Appointed to guide the project were Sun Jiadong, chief designer, veteran of many programs, most recently Beidou, and aged almost 80; Ye Peijian, designer; and Ouyang Ziyan, chief scientist. ¥1.4bn (€140m) were allocated, the cost to be kept down by the use of existing systems. Four broad aims were set down, to:

• image the Moon in three dimensions to determine its structure, topography, craters, history, and structural evolution;

• determine the contents and distribution of its chemical elements;

• measure the thickness of its regolith; and

• explore the particle and radiation environment around the Moon.

To organize the mission, a Lunar Exploration and Engineering Centre was established in 2005, directed by Hu Hao. To guide its scientific purpose, China set up a Lunar and Planetary Science Research Centre in the Institute of Geochemistry of the Chinese Academy of Sciences (this echoed the Vernadsky Institute in the Soviet Academy of Sciences which had a comparable function). This was Ouyang Ziyuan’s responsibility: he had graduated from university in 1956 and was the principal campaigner for the Chinese lunar program (indeed, his wish list of manned lunar missions was often mistaken in the Western press as an approved government plan). Ouyang Ziyuan had already published, in 1998, an article with his colleagues Wenzhu Lin and Shijie Wang called “Cosmochemistry” {Episodes, 18(1-2)) followed, in 2005, by Introduction to Lunar Science (2005, China Astronautic Press).

A Dong Fang Hong 3 comsat was adapted for the mission, to save the expensive construction of a completely new spacecraft. It weighed 2,350 kg but, because of the complex trajectory to be followed, half was fuel. The weight of the payload was small, drawing 161 W of power, and it was announced in spring 2007; the details are shown in Table 9.1. The data transmission rate was to be 3 MB/sec.

Following the mission required substantial investment in a ground tracking system. In spring 2006, construction began of a new tracking dish, 40 m across, 2,000 m atop Phoenix Mountain, Kunming, Yunan, which would work with other dishes near Shanghai and Xinjiang. Later, a 50-m dish near Beijing was added to the system. For practice, the European Space Agency (ESA) allowed China to use its tracking system to follow the European SMART 1 lunar mission. In 2011, China signed an agreement with Argentina for the use of its dish at the radio astronomy observatory at Felix Aguilar in San Juan [2].

Table 9.1. Chang e instruments.

Stereo camera to take three-dimensional images: resolution 120 m, swath 60 km, weight 31 kg

Ultraviolet imager

Interfering imaging spectrometer in 32 bands: resolution 200 m, swath 25.6 km

Laser altimeter: resolution 1 m, wavelength 1,064 nm, weight 11 kg

Gamma ray spectrometer: 300 keV to 9 MeV, to detect up to 14 chemical elements, weight 35 kg

Remote microwave radiometer to determine depth regolith, detect Helium 3: depth 30 m, resolution 0.5°C in 9.4 GHz, 19.4 GHz, and 37 GHz, aperture 50 cm (also called microwave sounder)

High-energy particle detector for protons 4-400 MeV, to measure heavy ions, helium, lithium, calcium, weight 2.4 kg

Low-energy solar wind ion detector up to 730 MeV, weight 7 kg

X-ray spectrometer: range 0.5-60 KeV

Speculation of Chinese ambitions to land on the Moon has been a regular feature of Western press coverage of the program since the flight of Yang Liwei. It has been amply fuelled by Ouyang Ziyuan, director of the Lunar and Planetary Science Research Centre, who has relentlessly promoted the concept of a Chinese lunar landing and base at any opportunity, domestic and international, leading uninformed Western commentators to confuse his campaigns with government intent. Confusion has been compounded by over-analysis: the Chang e lunar program mission sticker comprises a flying dragon, a waxing moon – and footprints – but these were not necessarily indicative of an early manned mission there. Chinese ambitions gained enormous traction when, on 17th September 2007, NASA administrator Mike Griffin told an audience in the Mayflower Hotel that the Chinese would beat the Americans back to the Moon.

China has long Earthly experience of bases far from home. That very year, in 2007, the country began its 24th expedition to Antarctica on board the exploration ship Xuelong, or “red dragon”, and there has been a Chinese base there, Zhongshan, since 1989 – the nearest possible Earthly analog. In October 2009, Dong Nengli of the Manned Space Engineering Program informed the International Astronautical Congress in Daejon, Korea, that conceptual studies of a manned lunar mission were being made. China was likely to look to the USSR for guidance, for the Soviet Union had, in the 1970s, detailed how a lunar base might be developed. The USSR had set down, in detail, no fewer than three models: the L-3M plan of the 1970s, which could put three cosmonauts on the Moon for between two weeks and a month; and two Moonbase sketches, Galaktika and the Zvezda.

In Academicians Envisaging the 21st Century, issued to mark the new millennium, Ouyang Ziyuan outlined the building of a lunar base from first landfall to a self­sufficient colony. If China could build bases at the Earth’s poles, it could do so on the Moon, he said. The chapter described how the lunar colonists would build their own solar power plants, extract minerals from the lunar soil, travel across the Moon in lunar roving vehicles, and make astronomical observations of the heavens. One function of the lunar base will be to observe climate change on the Earth continuously with images of 500-m resolution. At the time the book was published, both the director of the China National Space Administration, Luan Enjie, and the

chief designer of Chinese rockets, Long Lehao, made futuristic speeches about how, later in the century, China would venture on to Mars. During national science week, designed to stimulate children’s interest in science, the exhibits included a Chinese base on the red planet, complete with greenhouses and domes, and, in an adjoining exhibit, a robotic rover vehicle.

Indeed, China began the preliminary studies for manned lunar and Martian expeditions. He Xiaoying looked at how dust affected lunar modules as they came in to land, while Zhen Li and her colleagues outlined the new technologies that must be mastered for Mars, such as aero-capture, closed life-support systems, robotics, and communications [14]. They would be preceded by extensive robotic missions.

We know the next steps in the Chinese Moon program (Chang e 3 and 4 rovers; 5 and 6 sample returns) and the next planned Martian mission (Yinghuo 2, in 2015). After that, in Roadmap 2050, China projects a rover or a planetary science laboratory in 2020, a sample return in 2033, and a manned Mars landing by 2050. During the period from 2035, China intends to make its first robotic missions to Mercury, the asteroids, Jupiter, and Saturn, and send a probe to reach the heliospheric boundary at 100 AU. We may surmise the names of the next set of Chinese interplanetary spacecraft, for they will likely be based on those in ancient Chinese astronomy (Mars we already know) (Table 10.9).

The tracking infrastructure may be divided into domestic land stations, foreign land stations, and maritime stations. China first began space tracking soon after the Soviet Union launched Sputnik in 1957 and, in early 1965, Zhou Enlai made the first preparations for a ground tracking network for China’s own first satelhte. Two years later, construction began of seven ground stations at strategic points on the Chinese land mass, the main control center located in Weinan, Shaanxi, each station being equipped with tracking radars, signal receivers, optical trackers, data-processing systems, and control systems to send commands to the satellite. Later, more sophisticated and accurate laser trackers were introduced. The most westerly station was Kashi (also known as Kashgar) in the high western desert and this became designated the “number 1 tracking station” because it was the first station Chinese satellites would overfly on their west-to-east paths across the sky. For the communications satellites introduced in the 1980s, China built more ground stations: Nanjing (1975), Shijiazhuang (1976), Kunming (Sichuan) and later Urumqi (1982), Beijing (1983, the central station), and Llasa, Tibet (1984).

China’s main mission control is located in the city of Xian, famous for its underground army of terracotta soldiers, located at 34.3°N, 108.9°E. Dating to 1967, it was originally called the Satellite Survey Department and comprises a downtown mission control (photograph) and an out-of-town set of tracking arrays on a

plateau in the mountains, equipped with antenna farms, masts, and communications dishes. Chinese farmers may be seen gathering in wheat by hand on the terraces they share with the station. The downtown mission control room comprises television screens, consoles, plotters, and high-speed computers that follow, calculate, and predict the orbital paths of all Chinese satellites in orbit at a given time.

The ground tracking system is supplemented by stations designed to pick up signals from Earth resources satellites. The original such station was in Miyun (100 km north­east of Beijing), built in 1968 to receive data from the American Landsat and subsequently European, French (e. g. SPOT), and Japanese satellites. Later, ground stations were built in Guangzhou and Urumqi to receive data from the Feng Yun metsats and the American National Oceanic and Atmospheric Administration (NOAA) metsats. Chinese Earth observation satellites now transmit to three stations: Miyun (Beijing), Kashi (west), and a new station in the south at Sanya, on the southern tip of Hainan Island, between them forming three circles covering Chinese territory [3].

In addition to controlhng Chinese satellites in orbit, there is an important task in identifying and following satellites belonging to other countries that overfly China. Here, China Satellite Launch and Tacking General Control was set up in 1967, comprising the Beijing Aerospace Command and Control Centre and the Institute for Tracking, Command and Control in Luoyang, down the Yellow River from Xian, to monitor all overflying satellites from low Earth orbit out to 24-hr orbit.

By the 1980s, the space industry became ever more aware of the problem of space debris, which ranged from derelict satellites to discarded upper stages to paint flakes peeling off space equipment, with up to 30,000 items in orbit. There was a small, but real, danger that such debris could pose a hazard to manned flight so, in 2000, COSTIND was given ¥30m (€3m) to begin to assess and track debris in advance of the First manned spaceflight. With the help of computer modeling, a hazard avoidance system was devised that would warn controllers of any debris that might pose a danger to Shenzhou, so that it could be moved out of harm’s way in time.

One of the main weaknesses in China’s tracking system was a lack of overseas bases. By contrast, the United States had established from an early stage, with its many friendly overseas partners, a worldwide network of ground-based tracking stations to assist the manned space program and deep-space missions. Lacking allies overseas, the Soviet Union and China had to rely on communications ships, or comships. These were especially important when satellites were flying over southern latitudes, away from their northern hemispheric land masses. In the 1970s, two oceanographic ships, the Xiangyanghong 5 and the Xiangyanghong 11, were brought into use to track the early satellites.

As the space program expanded, it acquired both purpose-built ships and its own institutional form, Satellite Maritime Tracking and Control. The comships are called the Yuan Wang 1, 2, 3, and so on (the words mean “looking far into the distance”, or “long view” for short in Chinese). The first two Yuan Wang were dehvered in 1978 and were the mainstay of overseas tracking in the 1980s. Each was equipped with two 20-m-wide communication dishes, had an ocean-going range of 21,000 km, and could steam for 100 days at a time. Both ships were completely renovated in their home port of Shanghai in 1998-99.

Yuan Wang 3 was commissioned in 1995, a big ship of over 17,000 tonnes’ displacement, 190 m long, with nine decks and the appearance of a cruise liner. The Yuan Wang top deck is equipped with s-band antennae, arrays, and satellite dishes with a helideck from which weather balloons are launched. It has c-band and s-band monopulse tracking radars, cine-theodolite laser ranging and tracking, facihties for launching balloons, and communications in the high, ultra-long and ultra-high- frequency bands. Below deck are computer and control rooms, much like mission control on land. It is home to a crew of 350. Over the years, this ship came to adopt Davao in the Philippines as its port away from home, from which it would follow Yaogan missions (Chapter 6). It was joined by the Yuan Wang 4 in 1999, completing a four-strong fleet in time for the first Shenzhou mission. By 2005, it had steamed over 300,000 km on 18 missions. The even larger Yuan Wang 5 first went to sea in September 2007, with a displacement of 25,000 tonnes, constructed in the Jianquan

Launch sites 65

yard in Shanghai. Yuan Wang 6 joined the team on 12th April 2008 and its first operational voyage was the Shenzhou 7 mission.

Comships have drawbacks. They are expensive to operate (Russia decommis­sioned its fleet for lack of money). Conditions in the southern hemisphere’s seas are quite poor during April-October, which has the effect of limiting missions like the Shenzhou tests to the southern summer and northern winter when they are kinder. Their coverage is actually quite limited, 12% of the orbit for each, albeit at crucial points. For these reasons, China began to consider overseas ground stations, briefly operating a station in South Tarawa Atoll in the Pacific (1997-2003) and then making a mutual access agreement with Sweden for access to its stations in Sweden and Norway (2001).

In 2000, China began construction of its own first overseas land satellite station, in Swakopmund, Namibia. At first sight, this might appear to be a strange location, but retro-fire for a manned spacecraft descending to China takes place as it passes over the coast of south-west Africa. For Shenzhou 1 and 2, China positioned a Yuan Wang tracking ship off south-west Africa to prepare for and monitor these crucial maneuvers. A nearby land station, requiring fewer personnel and not being affected by rough seas, offered a cheaper and more secure alternative. China and Namibia signed an agreement for a tracking station at the Swakopmund salt works, on the road to Henties Bay, completed in 2001. The station comprised satellite dishes, control rooms, administration building, and support facilities. The two dishes – one of 5 m, the other of 9 m – reach 16 m above ground. The station had five permanent staff, expanding to 20 when missions were under way. Later, the overseas ground network was joined by a second overseas station in Pakistan in 2003. A couple of months later, the Italian Space Agency offered the use of its Malindi, Kenya site, providing an additional point of coverage just as the spacecraft go into re-entry (Italy used to launch spacecraft from an oil platform off the Kenyan coast). Later, Dongara, Australia, was added (Chapter 1).

The first attempt to launch a recoverable Earth satellite on the Long March 2 took place on 5th November 1974 and was a disaster. The rocket had barely lifted off before it began to sway from side to side and had to be destroyed in a fireball by the

range safety officer. The wire from the gyro to the control system had fractured – so it was later determined – and the control system had no basis for stabilizing the rocket. A year-long campaign to drive up quality was so extensive that the improved rocket was given a new designation: the Long March 2C.

The second attempt was made on 26th November 1975, when the first FSW 0 was launched into orbit from Jiuquan. Seven seconds after lift-off, the rocket turned towards the south-east. After 130 sec, the first-stage engine shut down. The verniers on the second stage ignited, explosive bolts fired to separate the two stages, and the first stage fell to the ground over uninhabited parts of Gansu. The second stage lit up, while small verniers continued to fire for a further 64 sec as the rocket coasted upward towards an orbital insertion point at 179-km altitude, 1,800 km downrange.

Due to a loss of pressure of the gas orientation system, it was decided to bring the first FSW home after only three days. As retro-fire approached on the 47th orbit, helicopters were scrambled to watch the cabin come in. The return to the Earth was problematical, the cabin being badly burned and approaching far from the originally intended spot. Although observers had been scattered on the mountaintops of Sichuan, no one saw a thing but, in Guizhou, four coal miners at lunch in their canteen were startled to spot a red-hot ball falling from the sky and crashing into trees. They found a blackened hulk in a crater. One of them threw a stone at the smoldering object and it bounced off with a metallic clang. The miners called the authorities. FSW was way off course and the cabin was very badly charred, indications of a less-than-perfect re-entry – but China had succeeded in recovering a capsule at the first attempt, like the Soviet Union many years earlier (the US experienced a dozen failures).

The Chinese designated the second set of missions the FSW 1 series, so this series was retrospectively but oddly named the FSW 0 program, the individual missions being numbered 0-1, 0-2, 0-3, and so on. Following the re-entry problems experienced with FSW 0-1, the cabin was redesigned, which took a year. The heat shielding material XF was extended to those parts of the cabin that had been badly burnt on the first mission. The second mission, in December 1976, achieved the landing accuracy intended. At headquarters, a plotting map marked the projected descent point while loudspeakers relayed the latest reports. Four helicopters were scrambled. A sonic boom from the returning cabin rumbled through the valleys of Sichuan. Sharp skywatchers noticed a black dot hurtle in from the north-west, splitting in two. One was the discarded heat shield, which was eventually found beside a road. The other was the cabin. Once the timer activated the parachute, the cabin could be seen gently descending, ending up in a vegetable garden on the side of a hill. One of the four helicopters found a flat spot 100 m away. The crew jumped out, mounted guard, began inspection, and removed the precious film. The third mission of the recoverable FSW satellite took place in January 1978 and was also successful; the post-flight announcement confirmed that remote sensing tests had been carried out.

There was a gap of over four years before the fourth mission appeared, the principal innovation being that on-orbit lifetime was extended to five days and new charge-couple device cameras were mounted to test the possibihties of transmitting

data in real time. FSW 0-4 appeared in September 1982 and further missions followed in August 1983, September 1984, October 1985, October 1986, and August 1987 (FSW 0-9). The charge-couple device transmissions were declared to be successful. The October 1985 mission took part in a general territorial survey of the land mass of China. FSW 0-8 was distinguished by coming down in a small inland lake, thus making it the first splashdown in the Chinese space program, although the lake concerned seems to have been thankfully quite shallow. The 1984-86 missions were land surveys taking more than 3,000 pictures using wide-angle cameras. It is difficult to assess the quality of photographs returned to the Earth by the early FSW imaging systems. Although the Chinese have published photographs of China taken from space, the satelhtes concerned have never been identified and, in some cases, American pictures have been used. Years later, the Chinese claimed that the FSW series had returned good-quahty, broad-scale survey images that had made an important contribution to mapping, land use, forestry, water resources, and problems of soil erosion.

FSW 0-9, the last of the early series, broke new ground, being the first mission to fly microgravity experiments and biology tests. Seven materials processing experiments with gallium arsenide semiconductors were flown, for the first time. FSW 0-9 was also the first to fly a Western commercial payload, carrying two small (15-kg) microgravity experiments for the French company Matra. The experimental boxes were handed back to Matra 10 days after recovery: one of them involved the testing of food growth and algae in orbit. A Chinese microgravity experiment was

carried, involving the smelting and re-crystallization of alloys and semiconductors. It is not clear whether the final FSW had any remote sensing role at all or whether it was devoted entirely to microgravity experiments. In the course of 1987-88, no fewer than 144 microgravity experiments were carried out for China, the German space agency, DFVLR, now the DLR (Deutsches Zentrum fur Luft und Raumfahrt), and the French company Matra [2]. Silkworms were carried into orbit in an experiment devised by Yang Tiande. The results were dramatic, with development of the embryo

two days more quickly than on the ground, a 50% reduction in hatching rates, the silkworms being 6% shorter, but the silk produced in orbit being longer, neater, and more reliable. Overall, the life cycle of the silkworm was two to three days faster in orbit. His experiment was repeated in 1992 on the longer mission of the Russian satellite Bion 10, which saw successful cocooning, evolution into moths, mating, and the laying of eggs, and on Bion 11. Cocoon weights were higher than the ground control sample. Seeds that took hits from cosmic rays grew faster and flowered earlier. Tomatoes had notable DNA mutation [3].

The success of communications satellites encouraged China to develop a range of applications satellites: weather forecasting in both polar and geostationary orbit (Feng Yun), Earth resources (Ziyuan, China Brazil Earth Resources Satelhte (CBERS), Huanjing), mapping (Tansuo, Tianhui), marine surveillance (Haiyang), and navigation (Beidou). These programs have become ever more specialized in recent years. Some may also have a military dimension (Yaogan) and they are also covered here. Minor applications programs, including micro-satellites, are also reviewed. The formal decision to establish an apphcation program dates to the early 1980s when the Chinese government adopted a decision Applied Satellites and Satellite Application [1].

POLAR WEATHER SATELLITES (FENG YUN 1, 3)

Accurate weather forecasting had always been important for a large country so dependent on agriculture but vulnerable to damaging storms and floods. China suffered heavily from storms, flooding, and weather-related natural disasters, with losses to the economy in the millions – so anything that could be done to reduce that figure would be helpful. The United States launched the first weather satellite in 1960 (Tiros) and the Russians followed with an operational system later (Meteor, 1969). The government approved the concept of a Chinese meteorological satellite in 1970. Development was impeded by the cultural revolution and funds were not allocated until 1978. In the meantime, China set up its first station to receive internationally available meteorological data in Beijing, stations being built subsequently in Urumqi and Guangzhou.

China’s first weather satellite was named Feng Yun (“wind and cloud”) and built by the Shanghai Academy of Space Technology (SAST). The Feng Yun 1 satellite was hexagonal, 1.76 m tall, 1.4 m wide, weighed 757 kg, and had two solar panels spanning 8.6 m. Although photographs were the primary product of the series, there were instruments to provide a three-dimensional atmospheric profile of temperature, moisture, cloud, and rain. The satellite had a scanning radiometer designed to monitor clouds, water color, crops, forests, and pollution, transmitting automatically in real

B. Harvey, China in Space: The Great Leap Forward, Springer Praxis Books,

DOI 10.1007/978-l-4614-5043-6_6, © Springer Science+Business Media New York 2013

time and by tape recorder. Small nitrogen-powered thrusters were used to ensure the satellite pointed the right way.

It was decided to fly Feng Yung into polar, Sun-synchronous orbit and orbit the Earth 14 times a day. It is polar because it flies almost across the poles and Sun – synchronous because it follows the same ground track each day and crosses the same point on the Earth’s surface at the same time each day. Targets are illuminated by the same Sun angle, making it easier to compare weather data from one day to the next. A new launch center was required for a satellite to enter polar, Sun – synchronous orbit. Accordingly, a former missile site near the industrial coal town of Taiyuan, south-west of Beijing, was selected.

With the Long March 2 having insufficient thrust and the Long March 3 too much, a new launcher was developed for the Feng Yun, the Long March 4. The Long March 4 was based on the highly reliable Long March 2C, but with a new, more powerful upper stage. Long March 4, 41.9 m tall at lift-off, with a thrust of 300 tonnes, had a small third stage using conventional fuels.

The first Chinese weather satellite was launched on 6th September 1988 and entered an orbit of 99.1°, 881-904 km. It soon sent back pictures of cyclones, rainstorms, sea fogs, and mountain snow. This first mission was less than entirely successful. One of the radiometers was fogged and the spacecraft failed after 39 days. Apparently, condensation in the spacecraft had not been fully removed before it left the Earth and this fouled up the sensitive radiometer.

Feng Yun 1-2 was launched two years later on 3rd September 1990 and it dropped off two balloons in orbit (Chapter 7). It was heavier (889 kg) but appeared
to suffer radiation damage in February 1991 possibly from a solar flare, but, after a 50-day struggle, ground control in Kashi performed a minor miracle by recovering the satellite fully. There was further radiation damage later in the year and the data eventually became unusable.

By way of a postscript, the upper stage of the launcher that had put Feng Yun 1-2 into orbit exploded on 4th October 1990 when propellants leaked through the bulkhead into the oxidizer and ignited. This was an unwelcome development, for the world’s space powers had begun to realize the threat which orbital debris of this kind caused to manned space station operations. The American space agency, NASA, had even formed an office in Houston, Texas, with the brief of trying to reduce space debris. In 1995, China joined the Inter Agency Space Debris Coordination Committee and, in 2002, 11 countries, including China, had signed a debris mitigation agreement. The same year, China held a national debris mitigation conference and the government allocated ¥30m (€2.5m) to the problem. In advance of the Shenzhou mission, China was tracking up to 9,131 pieces of debris that might pose a hazard. Precautions were taken to safe the CZ-4B upper stage to prevent its venting residual propellants.

The Chinese always made it clear that the first two spacecraft were tests before the system became operational with Feng Yun 1-3, successfully launched in May 1999. Its first images were returned the same day and, by July, good-quality pictures were flowing in on all channels. A top priority for the mission was to ensure a working life measured in years, rather than months. Many precautions were taken against radiation damage and the satellite was first sent to the Lop Nor nuclear test site for checking against a recurrence of the problems that had plagued its predecessors. Feng Yun 1-3 exceeded its design life: two years later, it was still working, in a stable condition, with good power supply and returning clear pictures, crossing China every morning at 8:30 am. The weather satellite carried a 10-channel Multichannel Visible and Infrared Scan Radiometer – four in visible wavebands, three in near

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Feng Yun image of sea ice clinging to the coast. Courtesy: COSPAR China.

infrared, one in short-wave infrared, and two in long-wave infrared, with a resolution of 1.1 m. In its first two years, it collected a range of information on floods, droughts, forest fires, and ice, its cameras picking out a sandstorm that blew from Mongolia into China. Because it had exceeded its design life and was continuing to work satisfactorily, its replacement satellite was delayed. Feng Yun 1­4, the last of the series, was eventually launched on 15th May 2002 and also carried a 10-channel scanning radiometer. In 2002, Feng Yun 1-3 and 1-4 played an important role in monitoring flood levels on the Huaihe River, the size of the flooded area being filmed, transmitted to the ground, and posted on the internet daily.

As a result of the Feng Yun 1 series, China was able to not only improve the timeliness and quality of weather forecasting, but also build satellite-based sea – surface temperature data, estimate the volume of rain in clouds, predict crop growth and yields, and compile a picture of urban heat islands, atmospheric smog and dust, algal blooms, forest pests, pollution, and desertification. The series was also used for scientific as well as applications objectives, such as the monitoring of high-energy charged particles (heavy ions, protons, and electrons) and as a radiation warning system (Chapter 7).

Feng Yun 1-3 achieved notoriety many years later when it was shot down – by China. The satellite had concluded its mission when it was decided that it should be the target of China’s first ever satellite attack. On 11th January 2007, as it passed over Xian, it was closely tracked by radar. At the point 45° over the horizon, a DF – 21 missile was fired from Xi Chang on an intercept trajectory just 94 min before local dawn but still in darkness. A few minutes later, as Feng Yun was in sunhght at 1,100 km, the missile, with pinpoint precision, slammed into the satellite and smashed it into hundreds of tiny pieces. Debris spewed outward at a velocity of up to 2,000 km/hr. The interception was an impressive demonstration of sensors, tracking technology, and computer systems. The Feng Yun target was less than 2 m across, even if its arrays spanned 9 m.

The explosion produced 900 trackable objects over 10 cm immediately, a 10% instant increase in total orbital debris, but with the prediction that the total number may come to several tens of thousands between 200 and 3,800 km. The altitude of the interception was so high that the debris would take thousands of years to fall back to the Earth; 1,951 main debris items were tracked by summer 2011. An impact with any one of them by a spacesuited astronaut would puncture the suit and cause immediate death. The debris was likely to orbit over 100 years and was described by

Nick Johnson, the world’s foremost expert, as the worst fragmentation event in orbit, with some debris over 10 cm likely to stay aloft for centuries. For 20 years, the space powers had been trying to reduce Earth orbital debris and it was exasperating to experience such a deliberate setback. Incidents grew in which the crew of the space station had to evacuate the main part of the station and wait in the Soyuz lifeboats until the danger passed. The State Department reported that it had issued no fewer than 677 collision warnings to space agencies worldwide arising from the Chinese explosion, which, according to NASA, now accounted for 17% of all debris in orbit [2].

The attack was reported quickly in the West and not admitted by the Chinese until a week later. State news agencies seem to have been caught quite off guard by the event. The political leadership shrugged off the militarization arguments of the Americans, but was quite stung by the unexpected criticism about orbital debris. There seems good reason to suspect that, whilst the military was authorized to make the test, it had not sufficiently briefed the leadership as to when it would take place

or the negative debris consequences. China later told the United States through back channels that it would not happen again. The Americans revealed later that they knew the test was coining but chose not to attempt to prevent it. As if to make good the problem, Chinese scientists in Tsinghua University began to study the use of hexagonal, square, and triangular meshes to capture unwanted orbital debris [3].

The test, whilst an impressive demonstration of a high-altitude, high-speed interception, attracted worldwide criticism. Western analysts pondered the precise nature and purpose of the Chinese challenge [4]. American criticism focused on China’s belligerent militarization of space, but the United States were on shaky ground, for they themselves had used an F-15 fighter missile to shoot down their own Solwind in 1985 and even maintained an anti-satellite squadron (76 Space Control Squadron at Peterson Air Force Base, Colorado). The Bush administration issued its National Space Policy in October 2006. This was not well received in China, for the policy appeared to claim unilateral hegemony in space – the right to deploy assets there and to deny it to anyone else. A year after this event, a missile from the USS Lake Erie shot down a decaying failed American spy satellite, NROL 21, officially to prevent its falling into enemy hands but possibly as a reminder to the Chinese.

With this uneasy checkmate, the situation rested a little. Then, in November 2011, the US-China Economic and Security Review Commission alleged that Chinese ground trackers on the Norwegian tracking station in Svalbard, Spitzbergen, had hacked into the American Landsat 7 and the Terra Earth observation satellites. Both had experienced the type of interference that one would associate with attempted hacking and, in the case of Terra, actually managed to take over control, although no control commands were subsequently issued. Republican presidential candidate Michelle Bachmann of Minnesota, presumably using information available to her as a member of the House of Representatives Intelligence Committee, alleged that

Table 6.1. Feng Yun 3 series instruments.

Visible and Infrared Radiometer (VIRR), 10 channels Infrared Atmosphere Sounder (IRAS), 26 channels Microwave Temperature Sounder (MWTS), 4 channels Microwave Humidity Sounder (MWHS), 5 channels

Medium-Resolution Spectral Imager (MERSI), 20 channels, resolution 250 m Solar Backscatter Ultraviolet Sounder (SBUS)

Total Ozone Unit (TOU)

Microwave Radiation Imager (MWRI)

Atmospheric Sounding Interferometer (ASI)

Earth Radiation Measurement (ERM)

Space Environment Monitor (SEM)

Solar Irradiation Monitor (SIM)

China had blinded American satellites with lasers. The committee published a list of Chinese attempts to interfere with satellites dating back to 2005, when they tried to jam satellites, followed in 2006 by laser dazzling of an American reconnaissance satellite and a French spacecraft [5].

With the Feng Yun 1 series complete, China moved on to the Feng Yun 3 series, 2,500-kg observation satellites with instrumentation as shown in Table 6.1.

The MWHS was a new instrument development by Li Jing with a team of 30 young scientists, based on his work on Shenzhou 4. The first Feng Yun 3, 3-1, was launched on 27th May 2008 on CZ-4C from Taiyuan into a 804-811 km orbit, 101.4 min, 98.8°. Soon, it was sending down 88 pictures daily, with a resolution of 250 m and a temperature measurement accuracy of 0.1 °С. The second flew on 5th November 2010 from Taiyuan and went into operation the following May. Its orbital plane was 130° apart from FY 3-1, so as to give afternoon coverage, the idea being that the series would alternate between morning and afternoon paths. The atmospheric sounder enabled China to build up a picture of atmospheric methane (CH4), one of the main greenhouse gases. In 2012, Zhang Xingying of the National Satellite Meteorological Centre pubhshed a six-year dataset of mid-tropospheric methane covering 2003-08. Its main findings were that levels of methane varied a lot over China, being lowest in the west (due to low levels of industry and agriculture) and south (where winds carry it out to sea), had seasonal summer and winter peaks, and reached especially high levels in 2007. The experiment should enable greenhouse gas to be accurately measured, located, and, hopefully, their reduction tracked as climate control measures take effect.

For later Feng Yun 3 satellites, China stated that there would be two variants: the AM and PM series, alternating between polar and 55° orbits. The original program envisaged two experimental and five operational satellites but, later, China announced that up to 12 would fly by 2020. Starting in 2013, a sub-variant would be devoted to tropical rainfall analysis.

Despite the interest of Zhao Jiuzhang in the space environment, dedicated spacecraft were slow to emerge. The first space environment program, started in 1988 and called Meridian, was ground-based using 15 locations, including Zhongshan base at the South Pole, and later extended to sounding rockets. Europe offered a new opportunity. China and Europe had first agreed a cooperation program in 1980 (Chapter 3), which took concrete form 12 years later when China made arrange-

ments with the European Space Agency to take data from the Cluster project, an upcoming major venture with four satellites to study the Sun’s interaction with the Earth’s magnetosphere. China may have spotted an opportunity to participate in an international scientific program at relatively low cost and, in 1997, China proposed its own complementary project, Doublestar, called Tan Ce or “explorer” in Chinese. A feasibihty study concluded in 1999 and the program was approved by the Chinese government in 2000, leading on 9th July 2001 to an agreement in Paris with the European Space Agency. Cluster was originally to fly in 1996, but the probes were blown apart when Europe’s Ariane 5 exploded on its maiden mission. The backup models were taken out of storage to fly into orbit on the Russian Soyuz in summer 2000, so Tan Ce was very timely.

The notion of multiple satellites to explore the magnetosphere was well established, the main example being the Russian Interball project in which two sets of satellites had explored the magnetosphere from 1994 to 1995. Like Interball, China’s Doublestar system also comprised two satellites – hence the title “Double­star” – and proposed, using similar instruments, that their findings be cross – referenced to those of Cluster. Doublestar was a complementary mission insofar as the Chinese planned to reach regions of the sky inaccessible to the Cluster probes and build up a three-dimensional picture. Tan Ce 1 was originally to orbit out to 8 Earth radii, but Chinese scientist Zuyin Pu proposed that be lengthened to 12 Earth radii so as to extend the Cluster data. Their orbits were synchronized in such a way that all six satellites would, from time to time, be in the same line to observe solar activity.

The Doublestar mission design was for a first, equatorial satellite concentrated on the Earth’s magnetic tail, while the second, polar satellite checked out the magnetic poles and the resulting auroras. The mission aimed to improve scientists’ knowledge of magnetic storms which can upset communications, radar, and navigation systems on the Earth. It was anticipated that each mission would last a year, this short length determined by the damage resulting from regular passage through intense radiation belts. The European Space Agency contributed a modest €8m to the mission in return for four hours a day of data over the planned 18 months of the missions. The instrumentation is detailed in Table 7.4.

These were small satellites, about 350 kg in weight, 1.2 m high, 2.1 m in diameter, with a solar array of 6.33 m2 able to generate 280 W, with a design life of 12­18 months. Ground receiving stations were configured to receive data in Beijing, Shanghai, and Villafranca, Spain, while data centers were established in Beijing, China; Toulouse, France; Noordwijk, the Netherlands; Didcot, Britain; and Graz, Austria. The program got under way very quickly, despite interruptions from the Severe Acute Respiratory Syndrome (SARS) medical emergency.

The equatorial satellite was launched first, lifting off from Taiyuan on a Long March 2C on 29th December 2003, broadcast on Chinese TV. It entered a highly elliptical orbit of 570-78,948 km, the furthest orbit ever achieved by China, inclination 28.5°. One boom did not deploy but this did not have a large negative impact. It made its first observations on 21st January 2004, a 6.1 solar flare. The next day, 12.6 Earth radii out, it noted that the pressure of the solar wind had

Table 7.4. Tan Ce instruments.

Both spacecraft

TC-1 equatorial/ tail

Active space potential controller Austria

Hot-ion analyzer France

TC-2 polar

Energetic neutral atom imager Ireland

Low-frequency electromagnetic wave detector China

increased by five times. Tan Ce 2 was duly launched on 25th July 2004, entering a somewhat different orbit, of 560-38,278 km, 90°, circling the Earth every 7.3 hr. By operating with Cluster, data could be collected from six data points. In August

2004, for example, Tan Ce 1 and 2 were in the trapped region behind the Earth, while the four Cluster satellites were further behind in the neutral sheet. In February

2005, by contrast, Tan Ce 1 was on the sunward side, Tac Ce above the Earth at the cusp, and Cluster in the magnetosheath.

The initial mission lasted a year to August 2005. By May 2006, ground controllers had received 175 GB from Tan Ce 1 and 145 GB from Tan Ce 2. Tan Ce l’s backup attitude controller failed during a big magnetic storm, but ground controllers were able to keep the spacecraft under control. Both missions were extended to September 2007, the official mission termination point. Tan Ce 1 decayed on 14th October 2007. Tan Ce 2 was lost in August 2007 but, to some surprise, was recovered that November.

The Tan Ce and Cluster missions led to at least 1,000 scientific papers. The International Academy of Astronautics (IAA) conferred the prestigious Laurels for Team Achievement Award on the Double Star/Cluster Team for providing unprecedented measurement capability and discoveries in geospace. The main fields covered by the two spacecraft were geomagnetic storms; magnetospheric sub-storms;

magnetic reconnection; the interaction of the solar wind with the magnetosphere and ionosphere; changes in the radiation belt, the ring current, and the plasmasphere; the plasma sheet; geomagnetic pulsations; space plasma; and the magnetosheath, magnetopause, cusp, and polar cap.

The first results of the mission were presented at a symposium on Cluster and Doublestar in Noordwijk, the Netherlands, in September 2005, which took in the results of 21 simultaneous magnetopause crossings. The initial scientific results from Tan Ce were:

• they confirmed the theory of magnetic reconnection in the Earth’s magneto­sphere; they found multiple reconnection sites and flux ropes 6.3 Earth radii out in the Earth’s fragmented magnetotail; Flux Transfer Events (FTEs) were noted at the points of reconnection, speeding at between 170 and 250 km/sec;

• they discovered 140 ion density holes in the solar wind upstream of the bow shock, several thousands of kilometers apart, in upstreaming particles;

• Tan Се 1 detected cracks in a neutron star crust during a starquake;

• they found density holes ahead of the bow shock;

• ultra-low-frequency waves made the magnetic field lines wobble; and

• low latitude is the best place for ultra-low-frequency waves to assist solar wind particles to penetrate the magnetopause [6].

Later, two detailed mission reports were issued [7]. The principal highlights were:

• Tan Се 1 recorded 516 tailward flow events at between 7 and 13 Earth radii and found eight magnetic flux ropes;

• individual magnetic storms were studied in detail, such as the “Halloween storm” of 31st October 2003 and the violent storm of 21st-22nd January 2005 (mach 5.4); Tan Се 1 observed a sub-storm on 12th October 2004, noting low-density, high-temperature ions originating from the ionosphere and flowing along the magnetic field – observations matched with the American Geotail;

• two oxygen-rich Bursty Bulk flows (BBFs) were observed during the magnetic storm of 8th November 2004;

• Tan Се 1 measured bursts of flows from the Sun, typically 48-103 sec during storms, their velocity (rising from 390 km/sec to 520 km/sec), and ion densities (ranging from 0.14 cm-3 to 0.28 cm-3);

• Tan Ce 2 observed 14 dawn chorus events in November 2004, the outbreak of radio noise associated with solar storms near the equatorial plane and their spreading to the mid and higher latitudes; and

• the polar spacecraft found vortex-like plasma flows at the boundary of the outer radiation belt and the ring current, going in opposite rotational directions.

FTEs were a feature of particular interest. Between February and April 2004, Tan Се 1 detected 27 FTEs, mainly at low latitudes, moving along the sides of the magnetosphere into the magnetotail, this time being matched with Europe’s Cluster spacecraft. Individual FTEs that affected both the four Cluster spacecraft and Tan Се 1 were studied, such as the 10-min FTE of 13th March 2004, enabling the profiling of an individual event in extraordinary detail. The typical duration of an FTE was measured: 130 sec.

A scientist who won particular recognition for his part in the mission was Zuyin Pu, who was awarded the 2010 COSPAR Vikram Sarabhai gold medal for his work on the anti-parallel reconnection of the magnetosphere at low and high latitudes, magnetic nulls, and energy transport from the solar wind to the magnetosphere, generating micro-pulsations [8]. Another was Susan McKenna-Lawlor of Space Technology Ireland, located on the campus of the National University of Ireland, Maynooth, who was responsible for Tan Ce 2’s NeUtral Atom Detector Unit (NUADU – the name of a Celtic warrior). NUADU was designed to monitor the ring current during geomagnetic storms and data were received up to mission end.

Tan Ce results: the ring current (right). Courtesy: Susan McKenna-Lawlor.

The unit featured the capability to record four Energetic Neutral Atom (ENA) distributions. These ENA data were used to remotely monitor the evolution of the terrestrial ring current during significant geomagnetic storms, thereby providing new insights into solar-related dynamic magnetospheric processes [9]. Bright ENA emissions recorded at the feet of terrestrial magnetic field lines during magnetic storm events indicated the presence of strong related increases in the fluxes of trapped energetic charged particles. ENA data recorded by NUADU and by NASA’s IMAGE/HENA instrument while viewing the northern and southern hemispheres during a major magnetic storm provided the first views of the ring current to be simultaneously obtained in both hemispheres.

The successor to Doublestar is the MIT mission, which stands for Magnetosphere- Ionosphere-Thermosphere, now in development. The purpose of MIT is to study:

• the processes that trigger magnetospheric storms and enable their recovery;

• the transport of ionospheric ions in the magnetosphere;

• the behavior of electrical fields during storms, with their temporal and spatial parameters;

• temperature variations during geomagnetic storms, their seasonal and diurnal variations; and

• the generation, propagation, and dissipation of large-scale gravity waves during storms.

Four satellites are involved: two in perpendicular polar orbits about the Earth at 600 km, called the thermosphere satellites (T1 and T2); a magnetospheric satellite in polar orbit between 1 and 7 Earth radii (M); and a solar wind satellite (S), in an equatorial orbit of 3-25 Earth radii. The instrument package has already been indicated and is outlined in Table 7.5.

Table 7.5. MIT instruments.

Magnetic field detector Electrical field detector Neutral particle spectrometer Plasma analysis system Neutral atom imaging suite Aurora imager

Limb aurora and airglow imager Atmospheric wind and temperature remote sensor

One will carry a new Neutral Atom Detector Unit following NUADU (NAIS-H) but featuring higher spatial resolution combined with a Low Energy Neutral Atom Imager (NAIS-L).