J. Jpn. Soc. Microgravity Appl. Vol. 22 No. 4 2005 (242–245) Keynote Paper Space Science in China Ji WU1 and Jin CHANG2 Abstract China started to develop space science in the early 1960s. from 1960s to 1990s we have developed some payloads for space science study onboard the spacecrafts which are not ˆxed in space science. In the 1990s the space science experi- ments including space astronomy have been done in the SZ spacecrafts. Up to now we have launched ˆve spacecrafts for space science experiment. Recently China's Geospace Double Star Exploration Program (DSP) is a very success- ful space science mission. More and more proposals, or potential projects have been proposed in recent two years. We try to brie‰y outline these new proposals, although most of them are in fact only in their conception studies. veloped and operated during every launch activities 1. Introduction and throughout each mission lifetime cycle. China started to explore the upper atmosphere using On the theoretical part, many of the state key sounding rockets and balloons in the early 1960s. Start laboratories have been established. The scientists have from the early 70's, right after China launched its ˆrst been using observation data from both abroad and satellite DFH–1, a series of scientiˆc/experiment satel- homemade satellites. China also built up some ground lites has been launch, the so called SJ series. For exam- observation facilities, including telescope for the Sun ple SJ–1 in 1971, SJ–2 in 1984, SJ–4 in 1994 and SJ–5 observation and radars for ionosphere observations. in 1999, etc. The SJ series are mostly dedicated to In 2000, Chinese government has issued a white space environment exploration and test the radiation paper on Chinese Space Activities. In this book, space environment eŠects. A good example is SJ–5. It has its science is listed together with space technology and main goal to study the single particle event in the LEO space application and one of the three major areas of on varies circuits. Besides it also was acting as the space activities in China. Under this framework, new microgravity experiment platform carried out a space science mission proposals are called right after double-layer ‰uid science experiment, in which a re- that, for example the Double Star Program in 2001, mote science operation of this experiment was real- and also recently, for example Chang'E–1 in 2004. A ized. ground based observation chain is approved by the Since late 1980s, retrievable satellites have been em- government in 2005. It involves 15 ground stations ployed for various kinds of scientiˆc experiments, such along 120 degree east meridian line and 30 degree west as natural resource discovery by means of remote sens- latitude line. They will be given a more detailed ing and microgravity experiments. In the later experi- coverage in the following sections under the topic of ments, many satisfactory results have been achieved in ongoing projects. crystal and protein growth, cell cultivation and crop Currently, missions proposed to next ˆve years plan breeding. Innovative achievements have been scored in are intensively evaluated and selected. After the ˆrst the study of basic theory of space science. round selection, a few proposals are given higher In 1992, Chinese government initialized the manned priorities than others and got the green light to con- space program. Before the ˆrst successful manned mis- tinue for Phase A studies. These mission proposals are sion, 4 unmanned test missions have been launched Hard X-ray Modulation Telescope (HXMT) in as- from 1999 to 2002. On the missions, the scientists have tronomy, KUAFU–space storms and aurora monitor- got a lot of opportunities to carry out scientiˆc experi- ing in geospace exploration, Small Explorer for Solar ments in the ˆeld of space astronomy, space physics, Eruption (SMESE) and Space Solar Telescope (SST). space environment eŠects test, earth remote sensing, Other proposals are kept for further study and for next microgravity science including basic ‰uid physics, round of evaluation in one year, such as DMS, AS- material science and life science. TROID I, SPORT and WIMS. The details of them are Along with the manned space program, the space given in the sections under the topic of proposed environment/space weather forecast has also been de- projects. 1 Center for Space Science and Applied Research, Chinese Academy of Sciences Beijing 100080, P.R. China (E-mail: wuji＠cssar.ac.cn) 2 Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008, P.R. China (E-mail: chang＠mail.pmo.ac.cn) 50 ― 242 ― Space Science in China – to probe the space environment in the vicinity of 2. Onging Projects the moon 2.1 Double Star Program (DSP) To accomplish the above goals, six scientiˆc pay- The Geo-space Double Star Exploration Program loads will be on board. They are, a stereo CCD camer- (DSP) is the ˆrst complete space science mission in a, a visible light band spectrometer, a laser altimeter, a China that starting from its orbit design to its payloads x-ray spectrometer, a four waveband microwave and application systems. It has been approved by the radiometer, a space environment detector package. To government on 2002 but with a early starting from mid better serve these payloads, a dedicated payload data 2001.ItisalsoajointprojectbetweenChinaandEu- management system is also employed. It composed by rope. The scientiˆc objective of DSP is to extend our a 1553B data bus controller, a 48 Gb solid state mass knowledge of the Earth's magnetosphere. It comprises memory, a power distributor and a remote data col- two Tan Ce (Explorer) spacecraft: lecting unit. The obiter is a 3-axis stabilized lunar Tan Ce 1 (TC–1) ‰ies in a highly elliptical equatorial pointing platform with capability of communicating orbit with apogee at 79000 km. Thus it will sample directly to the earth ground station and one year life- key regions on the day and night sides of the Earth time. The spacecraft including the payload is not turn- where the process of magnetic reconnection occurs. ing into its ‰y model manufacturing phase now and These reconnection processes dominate the dynam- everything shows that the planed launch date in 2007 ics of the magnetosphere. It was launched in 30 De- will be kept. cember 2003. The scientiˆc data from the payloads are mainly Tan Ce 2 (TC–2) ‰ies in a highly elliptical polar orbit received by a 50 meter antenna in Beijing (Miyun) and with apogee at 39000 km. Thus it will sample the po- backup with one 40 meter antenna in Kunming, Yun- larcapandcuspregionswhicharethemainregions nan province. There are more than one hundred scien- where energy from the Sun ‰ows into the mag- tists are awaiting for the ˆrst hand lunar exploration netosphere. Those ‰ows are largely controlled by the data coming down in 2007. reconnection processes to be studied by TC–1. It All the above is under development within the in- was successfully launched in 25 July 2004. stitutes of Chinese Academy of Sciences. Double Star provides measurements in key regions of 2.3 Meridian Project the magnetosphere. In addition, the orbits of the two The Meridian Project is a Chinese multi-station spacecraft are designed with coordination to ESA's chain along 1209E to monitor space environment, Cluster mission. Double Star and Cluster will make starting from Mohe, the most northern station in Chi- simultaneous observations when in separate but relat- na, through Beijing, Wuhan, Guangzhou and extend- ed regions. By exploiting such measurements, scien- ed to Chinese Zhongshan station in Antarctic. tists will improve their understanding of the mag- The project is composed with three systems, namely netosphere much better than from either mission a- monitoring, network and data transmission, research lone. A prime example will be when Double Star ob- and forecast. The monitoring system is further divided serves in the reconnection region on the dayside of the into four sub-systems. They are radio wave band ob- magnetosphere while Cluster observes in the so-called servation, optical observation, the Earth magnetism ``cusp'' region, where it can detect plasma ‰owing observation and sounding rocket observation. The ra- deep into the Earth's magnetosphere after entering the dio wave band observation sub-system includes the magnetosphere in the reconnection region. The two following instruments: non-coherent scattering radar, spacecrafts carry a total of sixteen scientiˆc in- MST radar, coherent scattering radar, interplanetary struments–eight from China and eight from Europe. plasma scintillation, middle wave radar and GPS The scientiˆc data are received by two ground stations receivers. The optical observation sub-system includes in Beijing (Miyun) and Shanghai (Sheshan) in China atmosphere lidar and interferometers. The Earth mag- and one ground stations in Spain (Villafranca) in Eu- netism observation sub-system includes many mag- rope. netometers. The sounding rocket sub-system will not 2.2 Chang'E–1 only carry out insitu measurement from 40 km upto Chang'E–1 is the ˆrst Chinese lunar mission. It aims 200 km, but also support the on site radar and other to launch a lunar orbiter in 2007. This mission is consi- remote sensing instrument for calibration. The sound- dered as the ˆrst step of China to go into the deep ing rocket launch site will be located in Hainan island space. The mission has four major scientiˆc objec- in south of China. tives. They are, The ground stations that will be build up or updated – to study lunar surface topography are: Mohe, Manzhouli, Harbin, Changchun, Beijing, – to analyze abundance of elements and distribu- Zhengzhou, Wuhan, Hangzhou, Hefei, Chengdu, tion of surface materials on the moon Lahsa, Shaoyang, Guangzhou, Hainan and Zhong- – to survey the global properties of the lunar shan.