空间科学学报

Closeby Habitable Exoplanet Survey (CHES): an Astrometry Mission for Probing Nearby Habitable Planets

JI Jianghui, LI Haitao, ZHANG Junbo, LI Dong, FANG Liang, WANG Su, DENG Lei, CHEN Guo, LI Fei, DONG Yao, LI Baoquan, GAO Xiaodong, XIAN Hao

2024, 44(2): 193-214. doi: 10.11728/cjss2024.02.yg03

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Abstract:
The Closeby Habitable Exoplanet Survey (CHES) employs state-of-the-art, high-precision astrometry and positioning technology at the microarcsecond level in space. Its primary objective is to conduct a thorough survey of approximately 100 FGK-type stars within the Sun’s proximity (within 10 parsecs), with the goal of detecting potentially habitable Earth-like planets or super-Earths. This pioneering mission involves a detailed census of habitable planets, providing intricate information on their numbers, true masses, and three-dimensional orbits. Notably, CHES marks a historic milestone as the inaugural international space exploration mission exclusively dedicated to the study of terrestrial planets within the nearby habitable zone. CHES’s payload features a cutting-edge optical telescope with a 1.2 m aperture, a field of view measuring 0.44°×0.44°, and a focal length of 36 m. The telescope utilizes a coaxial three-mirror TMA optical imaging system. Impressively, CHES is designed with a positioning measurement accuracy of 1 μas, solidifying its status as the most precise space exploration project globally in terms of positioning accuracy. To achieve the detection objectives of CHES, it is essential to refine and further substantiate the scientific goals through comprehensive argumentation. Overcoming three key technological challenges is crucial: advancing optical systems for large field of view, developing high-quality space telescopes with minimal distortion; breaking through measurement technology for stellar separations at the 10^–5 pixel level; and achieving high stability in satellite system attitude control and thermal control precision. CHES stands on the threshold of groundbreaking discoveries, with the exciting prospect of revealing 50 Earth-like planets. This announces a significant leap forward in China’s space science exploration technology.

International Space Station External Multi-payload Operational Mission Planning

SHAN Yadong, ZHANG Hanxun, DU Changshuai, ZHONG Hongen

2024, 44(2): 215-227. doi: 10.11728/cjss2024.02.2023-0047

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The external payload platform of the space station supports the deployment of many different types of payloads, which provides opportunities for massive space scientific research. However, with the continuous increasing number of external payloads and corresponding number of missions, and limited by resource constraints, it is necessary to develop scientific and reasonable mission planning to improve the operational efficiency of external payloads and the output of the science benefit. In this paper, the status of mission planning for external payloads on the International Space Station (ISS) is comprehensively analyzed, focusing on the external payload platform, payload types and characteristics, and methods for multi-payload operation mission planning. The current mission planning strategies, methods, and future development directions are analyzed. Based on the characteristics of the external payload platform of the China’s Space Station (CSS), this paper provides reference and suggestions for the subsequent mission planning of multi-payload system operation on the China’s Space Station from the aspects of overall payload design and mission planning methods.

Dependability Technology System for Autonomous Operation of Deep Space Exploration

DANG Wei, LUO Junwei, ZHENG Zuohuan, AO Liang, LI Bo, LI Peng, XIONG Shengyang, XU Pengcheng, SONG Hengxu, HU Jianqiao, FENG Yewei

2024, 44(2): 228-240. doi: 10.11728/cjss2024.02.2023-0138

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The “unrecognized and uncertain” is the basic feature of deep space exploration missions. A technology system of dependability for autonomous operation in deep space exploration was proposed based on the principle of “scientific value maximization”-oriented exploration and reliability as the core technology. The concept of reliability in the scenario of deep space exploration was analyzed and involved. A dependability systematic framework for autonomous operation of deep space exploration and its overall technical architecture of “demand-cognition-engineering” were proposed, which include precise sensing, optimal calculation, accurate decision-making and “quickly, precisely, exactly” execution. The reliability-oriented multi-physics deeply coupled white-box modeling and its high-fidelity technology, the complex network fault propagation mechanism and its high-confidence technology, the high-reliability assurance route for the application of COTS components in deep space exploration, the fusion mechanism of “model + data + knowledge” and its dynamic evolution technology for multi-agent health state management based on multiple fetal sensing phenomena were studied. The key technology of this technical system and the application verification of its minimum system in the satellite constellation were introduced, and the results show that the technology system proposed has high engineering value.

Study of Sample Imbalance in Deep Learning Modeling of Solar Flare Forecasting

ZHOU Jun, TONG Jizhou, LI Yunlong, FANG Shaofeng

2024, 44(2): 241-250. doi: 10.11728/cjss2024.02.2023-0028

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Solar flares, as violent eruptions occurring in the lower atmosphere of the Sun, exert significant impacts on human activities. Researchers globally have developed multiple prediction models for solar flares, employing empirical, physical, statistical, and other methodologies. There is an order of magnitude difference in the occurrence of different classes of flares. This makes it difficult for traditional convolutional neural network-based flare prediction models to capture M, X class flare features, which leads to the problem of low precision of high level flare prediction. With the breakthrough of deep learning technology in recent years, it has shown strong potential in modelling and prediction of complex problems and a number of works have begun to try to use deep learning methods to construct flare prediction models. In this paper, different deep long-tail learning methods are discussed by us to improve the precision of flare forecasting by controlling the variables for the long-tail distribution phenomenon in flare forecasting. The forecast performance of the model for M and X flares is tried to be improved from the perspectives of training set optimization, loss function optimization and network weight optimization. The experiments on SDO/HMI solar magnetogram data show that the precision of M, X class flare prediction is significantly improved by 53.10% and 38.50%, respectively, and the recall is increased by 64% and 52% compared with the baseline model trained by conventional methods. It shows that the treatment of the long-tailed distribution of data is crucial in the flare forecasting problem, and verifies the effectiveness of the deep long-tailed learning method. This method of improving the precision of tail class forecasts can be applied not only to the field of flare forecasting, but also can be transferred to the analysis of forecasting other typical events of space weather with long-tailed distribution phenomenon.

Application of F_10.7 Index Prediction Model Based on BiLSTM-attention and Chinese Autonomous Dataset

YAN Shuainan, LI Xuebao, DONG Liang, HUANG Wengeng, WANG Jing, YAN Pengchao, LOU Hengrui, HUANG Xusheng, LI Zhe, ZHENG Yanfang

2024, 44(2): 251-261. doi: 10.11728/cjss2024.02.2023-0040

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The F_10.7 index is an important indicator of solar activity. Accurate predictions of the F_10.7 index can help prevent and mitigate the effects of solar activity on areas such as radio communications, navigation and satellite communications. Based on the properties of the F_10.7 radio flux, the prediction model of F_10.7 based on BiLSTM-Attention is proposed by incorporating an Attention mechanism on the Bidirectional Long Short-Term Memory Network (BiLSTM). The Mean Absolute Error (MAE) on the Canadian DRAO dataset is 5.38, the Mean Absolute Percentage Error (MAPE) is controlled to within 5% and the correlation coefficient (R) reaches 0.987. It has superior prediction performance compared with other RNN models in both short-term and medium-term prediction. A Conversion Average Calibration (CAC) method is proposed to preprocess the F_10.7 data set observed by the Langfang L&S telescope in China. The processed data has high correlation with the DRAO dataset. Based on this dataset the forecasting effectiveness of the RNN series models is compared and analyzed. The experimental results show that both BiLSTM-Attention and BiLSTM models have significant advantages in predicting the F_10.7 index and show excellent predictive performance and good stability. The BiLSTM-Attention model has the highest prediction accuracy when forecasting future first-day data, with MAE and MAPE of 11.10 and 8.66, respectively, and the MAPE is always within 15% in the short- and medium-term forecasts. This shows that the proposed model has high generalization ability and can effectively predict the F_10.7 data set of DRAO and L&S.

Analysis of the Nighttime Variation Characteristics of Mesospheric Ozone and Correlation with Solar Activity

LIU Dan, WU Zhijing, YANG Junfeng, CHENG Xuan, WANG Jianmei, ZHANG Yiming, HU Xiong

2024, 44(2): 262-269. doi: 10.11728/cjss2024.02.2023-0061

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The satellite ozone data of ENVISAT-1/GOMOS (Global Ozone Monitoring by Occultation of Stars) and TIMED/SABER (Sounding of the Atmosphere using Broadband Emission Radiometry) are analyzed to provide a statistical analysis of the distribution of ozone in the tropical mesosphere (60～110 km) at night (20:00 LT－24:00 LT) and explore its correlation with the 27-day solar cycle with HAMMONIA (Hamburg model of the neutral and ionized atmosphere). Both observations and model indicate that the nighttime ozone in the mesosphere peaks at 95 km and there is a semiannual oscillation in the upper mesosphere; Comparison with Lyman-α solar radiative forcing data over the same period shows that upper mesospheric (above 80 km) ozone may be inversely correlated with solar forcing, and lower mesospheric ozone may be positively correlated with solar forcing.. In order to better explore the correlation with solar activity, the ozone data were processed by filtering, and it was found that the inverse correlation between ozone at 95 km and Lyman-α was more significant. This correlation is more pronounced when long-term and short-term fluctuations are removed, especially in the months before and after the period of maximum amplitude of the 27-day solar radiative forcing cycle (around January and July 2004). Although the observations and the model results share some common features in the temporal and spatial distribution of ozone variations with months, large differences are found in the values of the peaks where the amplitude of ozone sensitivity is greatly underestimated by the model.

Laboratory Thermal Emission Spectral Measurement and Calibration Methods for Planetary Science Research

YANG Yazhou, MILLIKEN Ralph E, BRAMBLE Michael S, PATTERSON William R, ZOU Yongliao, LIU Yang

2024, 44(2): 270-286. doi: 10.11728/cjss2024.01.2023-0116

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Accurate information regarding the surface composition is crucial for understanding the formation and evolution history of planetary bodies. Visible and near-infrared remote sensing spectroscopic techniques have long been used for the detection of surface composition. However, in the thermal infrared spectral range, various types of planetary surface materials exhibit richer spectral features. With the development of thermal emission spectroscopic techniques, it has been increasingly used in planetary exploration. Particularly, in the ongoing and planned asteroid exploration missions, thermal emission spectrometers are employed as key payloads. In order to better interpret the thermal emission spectral data to be obtained in the future, it is essential to establish scientifically reasonable data processing and calibration schemes. This paper provides a comprehensive overview on the design of thermal emission spectral measurement devices for planetary science research, the measurement process, and data reduction methods. To obtain accurate emissivity spectra data, the challenge of distinguishing sample radiation signals from instrument radiation during thermal emission measurements must be properly addressed first. Especially, for measurements conducted under low-temperature and vacuum conditions that are similar to the surface conditions of the Moon and asteroids. This paper proposes and demonstrates a data reduction method based on interferograms, which are the original signals measured by FTIR spectrometer. This method can effectively separate the actual radiation signal from the samples, thus yielding more accurate emissivity spectra data. The insights derived from this study can serve as valuable references for the development and construction of thermal emission measurement devices and can facilitate the processing and scientific interpretation of data from future missions such as Tianwen-2.

Near-Earth Asteroid Impact Event Disposal Rules and Processes

HONG Yu, CHEN Yongqiang, CAI Tingbin, CHANG Xiao, XU Liang, JING Hongbao

2024, 44(2): 287-298. doi: 10.11728/cjss2024.02.2023-0064

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In response to the shortcomings in the areas of disposal rules, coordination mechanisms, and operational procedures in China’s research on the defense of near-Earth asteroids, a simulation strategy for asteroid defense is proposed to meet the increasing demand for asteroid defense and disaster relief. Based on the current development status of asteroid defense at home and abroad, the gaps in China’s asteroid defense are analyzed. From the perspectives of mechanism establishment and coordinated emergency response, the simulation and deduction of asteroid defense at home and abroad are analyzed. Based on the current research status at home and abroad, a set of asteroid defense simulation and deduction plans are designed, and an organizational structure for China’s asteroid defense exercises is proposed, including three levels: guidance layer, event disposal layer, and business support layer, providing basic organizational support for asteroid defense exercises. The emergency response mechanism and general disposal rules for asteroid impact events are proposed, providing a rule basis for the disposal of events and the operation of each level in the organizational structure. The simulation scenarios are initially designed to verify the mechanisms and rules, providing a reference for the organization and implementation of near-Earth asteroid defense work.

Distribution and Characteristics of Martian Precipitating H-ENA

ZHANG Yiteng, LI Lei, XIE Lianghai, GOU Xiaochen, FENG Yongyong

2024, 44(2): 299-308. doi: 10.11728/cjss2024.02.2023-0044

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Abstract:
Energetic Neutral Atom (ENA) is generated by charge exchange between energetic ions and background neutrals. As Martian exosphere extends far above the bow shock, hydrogen ENA (H-ENA) produced by solar wind proton may enter the lower atmosphere directly, depositing mass and energy in the atmosphere. Based on the single-fluid multispecies MHD model and exosphere model, this paper calculates the spatial distribution of the precipitating H-ENA flux at the height of 200 km on Mars, evaluates the particle and energy deposition rate of the precipitating H-ENA under different solar wind conditions, analyzes their controlling factors. The results show that the solar wind H-ENA generated upstream of the bow shock is less affected by the crustal fields, and shows a cosZ distribution. As a major mass and energy source, the precipitating solar wind H-ENAs account for 59% particle deposition and 81% energy deposition of the total precipitating ENAs. Magnetosheath H-ENA generated in the magnetosheath is greatly affected by the crustal fields, and their precipitating flux decreases significantly above the strongest magnetic anomalies. The precipitating H-ENA flux is proportional to the upstream solar wind flux, and 2.1%～3.5% of upstream solar wind protons are estimated to be converted into the solar wind H-ENAs.

Research Progress of Lunar In-situ Water Production Techniques

ZHANG Peng, LIU Guanghui, LIU Xin, ZHANG Guang, ZHENG Haibo, DAI Wei, WANG Zhi, NIU Ran, BO Zheng, GAO Ming

2024, 44(2): 309-317. doi: 10.11728/cjss2024.02.2023-0006

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Abstract:
With the continuous advancement of deep space exploration, lunar exploration will be the first step for mankind to carry out interplanetary exploration and expand living territory. The lunar in-situ resource utilization will be a key technical approach to support manned exploration and long-term survival on the Moon surface. Almost all space powers are carrying out continuous research on lunar in-situ water production technology, and China has also listed lunar surface in-situ water production as one of the key technologies for lunar exploration missions. Lunar in-situ water production can be mainly divided into two methods: polar water ice exploration/extraction and hydrogen reduction of lunar regolith. The water ice resources that had been detected are mainly located in the lunar polar region, with uneven distribution and great difficulty in extraction method. Many different types of polar water ice exploration and extraction schemes have been put forward, but the actual effect needs to be verified by sufficient verification experiments and the lunar in-situ test. Hydrogen reduction of lunar regolith can be used for in-situ water production, and its working conditions are not limited by the region, and its application scope is wide. However, there are some remaining technical limitations such as extreme reaction condition requirements and high energy consumption, which implies urgent demand to make breakthroughs in energy conservation and effective ingredient enrichment. Thus, according to the development strategy deployment of lunar exploration missions and the requirements of in-situ water resource acquisition technology in the future, some suggestions are put forward on developing the key development path of in-situ water resource acquisition technology in the future. Target areas for future exploration missions, in-situ energy acquisition scheme, security and reliability of different technologies will be used as the main basis for different technology selection. It is hoped that this work will provide guidance for in-situ resource utilization in future lunar exploration missions.

System Design of Millimeter Wave Atmospheric Ozone Radiometer

BAN Lei, HE Jieying, ZHANG Shengwei

2024, 44(2): 318-325. doi: 10.11728/cjss2024.02.2023-0053

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Abstract:
Stratospheric ozone concentration has an important impact on global climate change and ecological environment. Hyperspectral millimeter wave radiometer with spectral analysis capability is a passive microwave remote sensor used to detect atmospheric trace gases. It can effectively detect the vertical profile of atmospheric ozone and has very important application value in the field of space earth science. In this paper, a new hyperspectral millimeter wave ozone radiometer system for detecting stratospheric ozone absorption lines is developed. The system structure includes RF receiver and digital spectrum analyzer. The RF receiver part uses a superheterodyne structure to obtain a 142.175 GHz ± 100 MHz bandwidth signal. The digital spectrum analysis part uses a high-performance analog-to-digital converter to sample the input analog signal at 5×10⁸ sample·s^–1. The quantization bit is 14 bit and the 3 dB bandwidth of the input signal is 200 MHz. The signal power spectrum is obtained by high-performance Field Programmable Gate Array (FPGA), and the number of detection channels is 16384, and the spectral resolution reached 12.2 kHz. This paper introduces the design scheme, device selection and test method of the key modules of the radiometer system. It is concluded that the system sensitivity and various indicators can meet the requirements of atmospheric ozone inversion, and the correctness of the system design is verified by conducting atmospheric detection experiments and comparing the experimental results with the simulation results of Atmospheric Radiative Transfer Simulation Software (ARTS). The radiometer system meets the application requirements of stratospheric ozone concentration monitoring, early warning and climate change research.

Analysis of Sea Surface Backscatter Coefficient Errors and Its Effects for the CFOSAT Scatterometer

DONG Ying, LIN Wenming

2024, 44(2): 326-334. doi: 10.11728/cjss2024.02.2023-0144

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Abstract:
Noise is a key factor that affects the accuracy of spaceborne scatterometer backscatter coefficient (σ⁰), as well as the retrieved sea surface wind quality. In general, the scatterometer σ⁰ measurement error is attributed to both instrumental noise and geophysical noise, which are expressed in terms of normalized standard deviation (K_p). In this paper, the instrumental noise (K_pc) and the geophysical noise (K_pg) are analyzed as a function of sea surface wind speed, incidence angle, spatial resolution and offshore distance for the China-France Oceanography Satellite Scatterometer. The result shows that the variability of sea surface wind field is large under low wind conditions, so the geophysical noise dominates the measurement error of radar backscatters. Notably, the larger the grid size of Wind Vector Cell (WVC), the more inhomogeneous the sea surface wind, such that the K_pg value increases as the WVC size, but at the same time, the larger the wind cell grid and the larger the number of independent observation samples, the smaller the K_pc. While under high wind conditions, the variability of sea surface wind is small, and the contribution of instrument noise and geophysical noise is similar. Regarding the sensitivity of measurement error to the incidence Angle, K_pc and K_pg show a minimum value at the incidence angle of 40°, which is consistent with the antenna gain pattern. Finally, the relationship between the backscatter measurement error and the offshore distance is studied in order to clarify the feasibility of near shore wind field inversion for the CSCAT. The results show that the observation error generally increases as the offshore distance decreases, indicating that the near-shore geophysical noise is non-negligible for the scatterometer measurements approaching to the coastal line. In summary, the results presented in this paper reveal the influence factors of scatterometer σ⁰ measurements, which are relevant for better understanding the wind inversion and quality control of CSCAT, notably near the coastal areas.

Study on the Active Regulation Mechanism of Laser Photothermal Effect on Thermocapillary Convection of Double-layer Fluid

DUAN Wenhao, ZHOU Xiaoming, CHEN Qisheng

2024, 44(2): 335-345. doi: 10.11728/cjss2024.02.2023-0036

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Abstract:
Active control of thermocapillary convective instability is a frontier scientific issue in the field of microgravity hydrodynamics and heat and mass transfer. In order to achieve effective control of thermocapillary convective instability of double-layer fluid, this paper innovatively proposes to use laser photothermal effect to actively control flow, the regulation mechanism of laser photothermal effect parameters (laser beam position, laser power and spot size) on the instability of double-layer thermocapillary convection are also studied. The calculation results show that the adjustment of laser power and spot size can significantly change the convective vortex structure in the spot area and weaken the vibration amplitude of temperature wave. Under certain working conditions, the temperature fluctuation range near the heat source changes significantly from 0.7 K to 0.1 K. The amplitude of temperature oscillation decreases first and then increases with the increase of spot size. The adjustment of the laser position can affect the position of the local convection vortex in the liquid layer, and then change the convection intensity on both sides of the laser position, so as to realize the control of the oscillating and unstable flow in the local region, the effective control of thermocapillary convection of double-layer fluid can be realized through the reasonable selection of photothermal effect parameters.

Dynamic Characteristics of Airship Envelope Material with Concentrated Mass

CHENG Jingsong, WANG Sheng, NIE Ying, SONG Lin

2024, 44(2): 346-355. doi: 10.11728/cjss2024.02.2023-0008

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Aiming at the design and analysis of stratospheric airship rigid and flexible integrated large complex structure system, this paper carried out the simulation analysis of dynamic characteristics of airship envelope material with concentrated mass. The structural parts with high stiffness and relatively concentrated mass are simplified as concentrated mass. The airship envelope is simplified as a biaxially stretched cross envelope material sample. Firstly, the influences of the number of open arm slits on the stress transfer uniformity in the central region of the cross envelop material sample are analyzed. Then the influences of pretension, mass and concentrated mass of the size on the natural frequency of cross film material sample are analyzed. The influence of the mass and concentrated mass of the size on the natural frequency of the airship capsule is also reflected. The results show that the uniformity of stress transfer in the central region of the cross envelop material sample is better with the increase of the number of arm slits. When the number of arm slits is 3, the proportional coefficient of stress transfer uniformity is 0.943. In addition, the natural frequency of the sample increases with the pretension increase, decreases with the mass of the concentrated mass increase, and increases with the side length of the connection between the concentrated mass and the sample increase. The fundamental frequency of the sample is independent of the height of the concentrated mass, but the second and third order frequencies decrease with the height of the concentrated mass increase. The second and third order frequencies are significantly more affected by various physical quantities than the first order. Under the condition of the same pretension and mass, the influence of the height of the concentrated mass on the second and third order frequencies of the cross envelop sample is higher than that of the side length. The research results provide a theoretical basis for the overall design and analysis of airship structure and the further dynamic experiments of airship envelope materials with concentrated mass.

Space-based Distributed Optical Synthetic Aperture Techniques

WANG Xiaoyong, ZHANG Jiafu, LI Ling, GUO Chongling

2024, 44(2): 356-367. doi: 10.11728/cjss2024.02.yg06

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The exploration and study of habitable zone planets is one of the hot research fields of exoplanets in recent years. The exploration of habitable planets near the solar system is of great significance to the study of the origin of life and has become the main theme of exoplanet exploration. As an important means of detecting exohabitable planets, space-based distributed synthetic aperture technology has become a hot spot in the research of advanced optical technology. In this paper, the technical principle of space-based distributed optical synthetic aperture system based on Michelson interferometric imaging is discussed in detail, and the development of typical distributed synthetic aperture systems at home and abroad is introduced. The technical challenges involved are demonstrated.

Simulation and Experimental Validation of Charge-driven Extreme Ultraviolet Photoelectric Effect

WANG Zidong, ZHOU Bin

2024, 44(2): 368-378. doi: 10.11728/cjss2024.02.2023-0038

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The test masses of the inertial sensor is the core of the precision gravity measurement system. The surface of test masses accumulates charges due to continuous injection of high-energy particles from space, which generates stray noise under the action of the internal electromagnetic field of the sensor and affects the precision gravity measurement results. According to the principle of photoelectric effect, use UV LED to generate extreme ultraviolet light to irradiate the electrodes of an inertial sensor and the surface of the test masses, and applying an appropriate electric field between the electrodes, it is possible to change the charge amount of the test masses without external forces and under non-contact conditions. Based on the simplified electrode model of the parallel plate capacitor, this paper carried out theoretical modeling and simulation of the extreme ultraviolet charge driving process. Based on this, a set of charge driving verification test system was designed and constructed, and experiments were carried out on the effects of light power and bias voltage on the charging and discharging rates and AC charge driving. The experiment proved that the charge-discharge rate is proportional to the extreme ultraviolet light power, and its quantum yield changes with the electric field strength between the plates. Ultimately, a stable control of the test masses discharge rate between 0.31 pC⋅s^–1 and 0.76 pC⋅s^–1 and charge rate between –0.05 pC⋅s^–1 and –0.17 pC⋅s^–1 can be achieved. The theoretical model of charge-discharge rate proposed in this article for the test masses is consistent with the results of ground experiments, which can strongly support the development of charge management and control systems.

Integrated Thermal Control System for Space Platform and Fractionated Payload

WU Zishuai, ZHANG Chengdong, LEI Zhibo, ZHAI Zaiteng, YAO Jian

2024, 44(2): 379-385. doi: 10.11728/cjss2024.02.2023-0041

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With the development of space exploration, combined spacecraft which can implement more complicated targets through fractionated payload or part of the spacecraft separated from the space platform have been in urgent need. Space platform provides carriage service for the fractionated payload or part of the spacecraft before separation. Under the hypothetical space platform and fractionated payload conditions, the paper proposed an integrated thermal control system for it, simultaneously, simulations of several cases such as thermal control efficacy for the payload during storage stage, the thermal impact between the space platform and the fractionated payload, and the temperature variation of the platform during separation were carried out. Moreover, the steady-state simulations and thermal mathematic model were verified through thermal vacuum test. Thermal simulations and thermal vacuum tests generate the scheme characters of the temperature and thermal fluxes between the platform and fractioned payload. The whole figures of the simulations and test results proved the rationality and effectiveness of the system, meanwhile, verified the feasibility of the thermal vacuum test method for the thermal coupled space platform and fractioned payload while would be independent during thermal vacuum test, which can be as a reference of such spacecraft cases.

2024 Vol. 44, No. 2

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