Progress of radio occultation exploration of Mars
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摘要: 火星是地球的姊妹星,研究火星对了解火星、地球乃至太阳系的演化具有重要意义. 自从1964年美国水手4号发射,首次成功地运用无线电掩星技术探知到火星的环境特征之后,国际上不少的火星任务都开展了掩星实验,取得了重要进展. 本文依据采用了无线电掩星技术进行勘探的火星探测器发射时间顺序展开调研,针对具有开创性的水手系列、火星全球勘测者、火星快车、火星大气挥发演化探测器、天问一号等,梳理分析和总结了各任务的火星无线电掩星方式以及所获取的廓线数量、位置分布、获取方式等产品信息,以及部分相关的研究结果. 本文还分析了当前火星无线电掩星探测方式存在的局限性,并探讨了可能的对策. 火星无线电掩星后续可重点考虑多颗星-星掩星结合星-地掩星方式形成掩星星座;并通过选用适当的信号探测频率、改进反演算法等方式进一步提高掩星质量;火星掩星探测手段还可与火星顶部探测雷达、直接探测等手段相结合,发展火星多源数据融合技术. 随着探测方式的不断改进,无线电掩星探测将是火星探测的重要手段. 未来会有数量越来越多、时间与空间覆盖越来越全面、精度越来越高的掩星数据用于火星的整个空间环境研究,包括大、中尺度乃至小尺度结构的特征与演化规律都将被人类掌握.Abstract: Mars is the sister star of Earth. Studying Mars is important to understand its evolution as well as that of Earth and even the solar system. Since the launch of American Mariner 4 in 1964 and the first successful use of radio occultation technology to explore the environmental characteristics of Mars, many international missions to Mars have conducted occultation experiments and made important progress. This article investigates Mars probes based on their launch time sequence, which utilized radio occultation techniques for exploration, focusing on groundbreaking missions such as the Mariner series, Mars Global Surveyor, Mars Express, Mars Atmosphere and Volatile Evolution, and Tianwen-1. We review, analyze, and summarize the product information, including the number and distribution of profile measurements, and the methods of acquisition obtained from each mission's radio occultation. Additionally, this article analyzes the limitations of the current Mars radio occultation approaches and explores possible countermeasures. Mars radio occultation can be further improved by considering the mode of star-star occultation combined with star-ground occultation to form occultation constellation, choosing an appropriate signal detection frequency, and improving the inversion algorithm. It can also be combined with the Mars top detection radar and direct detection means to develop multi-source data fusion. With the continuous improvement of detection modes, radio occultation detection will be an important tool for Mars exploration in the future. Detections will grow in number and become increasingly more comprehensive in time and space coverage, and more accurate occultation data for the entire space environment of Mars will be obtained, including large, mesoscale, and even small-scale structure characteristics and evolution laws.
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Key words:
- radio occultation /
- Mars /
- deep space exploration /
- space astronomy
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图 1 火星无线电掩星示意图(修改自Withers and Moore, 2020)
Figure 1. Schematic diagram of Mars radio occultation (modified from Withers and Moore, 2020)
图 7 MAVEN电子密度廓线:太阳天顶角70°(2022-02-22,黑);77°(2022-03-04,洋红);92°(2021-11-02,橙);97°(2021-12-06,红);102°(2022-04-30,绿);107°(2021-07-12,蓝)
Figure 7. Electron density profiles of MAVEN at solar zenith angles of 70° (February 22, 2022, black); 77° (March 4, 2022, magenta); 92° (November 2, 2021, orange); 97° (December 6, 2021, red); 102° (April 30, 2020, green); 107° (July 12, 2021, blue)
表 1 国际上发射的火星掩星探测任务一览表
Table 1. List of international Mars occultation missions
发射时间 任务名称 所属国 任务探测方式 探测波段 结果 1964-11-28 水手4号(Mariner - 4) 美国 飞越 S波段 成功 1969-02-25 水手6号(Mariner - 6) 美国 飞越 S波段 成功 1969-03-27 水手7号(Mariner - 7) 美国 飞越 S波段 成功 1971-05-30 水手9号(Mariner - 9) 美国 环绕 S波段 成功 1975-08-20 海盗1号(Viking - 1) 美国 环绕+着陆 S、X波段 成功 1975-09-09 海盗2号(Viking - 2) 美国 环绕+着陆 成功 1996-11-07 火星全球勘测者(MGS) 美国 环绕 X、Ka波段 成功 1996-12-04 火星探路者
(Mars Pathfinder)美国 着陆+巡视 X波段 成功 1998-07-04 “希望”(Nozomi) 日本 飞越 S、X波段(Nakamura et al., 1999) 失败 2001-04-07 火星奥德赛
(Mars Odyssey)美国 环绕 X波段 成功 2003-06-02 火星快车
(Mars Express)欧空局 环绕+着陆 S 、X波段 部分成功 2003-06-10 勇气号(Spirit) 美国 巡视 X波段(Callas, 2015) 成功 2003-07-08 机遇号(Opportunity) 美国 巡视 未知 成功 2005-08-12 火星勘察轨道器(MRO) 美国 环绕 X、Ka波段 成功 2007-08-04 凤凰号(Phoenix) 美国 着陆 未知 成功 2011-11-26 火星科学实验室(MSL)/好奇号 美国 巡视 X波段 成功 2013-11-05 火星轨道任务(MOM)/曼加里安 印度 环绕 未知 成功(张扬眉,2013) 2013-11-18 火星大气与挥发演化探测器(MAVEN) 美国 环绕 X波段 成功 2016-03-14 火星生物学2016(ExoMars2016) ESA/俄罗斯 环绕+着陆 未知 部分成功(王帅和张扬眉, 2016) 2020-07-20 阿联酋火星任务(EMM) 阿联酋 环绕 未知 成功(王帅,2020) 2020-07-23 天问一号(Tianwen-1) 中国 环绕+着陆+巡视 X波段 成功 -
[1] Ao C O, Edwards C D, Kahan D S, et al. 2015. A first demonstration of Mars crosslink occultation measurements[J]. Radio Science, 50(10): 997-1007. doi: 10.1002/2015RS005750 [2] Blanchard R C, Desai P N. 2011. Mars Phoenix entry, descent, and landing trajectory and atmosphere reconstruction[J]. Journal of Spacecraft and Rockets, 48(5): 809-822. doi: 10.2514/1.46274 [3] Callas J L. 2015. Mars Exploration Rover Spirit end of mission report[R]. Pasadena, California: California Institute of Technology (Jet Propulsion Laboratory). [4] 曹雨田, 牛丹丹, 崔峻, 等. 2021. 金星与火星电离层研究现状概述[J]. 地球与行星物理论评, 52(5): 528-542 doi: 10.19975/j.dqyxx.2021-024Cao Y T, Niu D D, Cui J, et al. 2021. Overview of the ionosphere study of Venus and Mars[J]. Review of Earth and Planetary Physics, 52(5): 528-542 (in Chinese). doi: 10.19975/j.dqyxx.2021-024 [5] Cheng Y, Lin X, Shen X H, et al. 2018. Analysis of GNSS radio occultation data from based on satellite ZH-01 [J]. Earth and Planetary Physics, 2 (6): 499-504. doi: 10.26464/epp2018048 [6] 杜起飞, 孙越强, 陶鹏, 等. 2009. 用于火星电离层探测的星-星无线电掩星技术[J]. 物理, 38(10): 717-721 doi: 10.3321/j.issn:0379-4148.2009.10.004Du Q F, Sun Y Q, Tao P, et al. 2009. Star-star tomiotation technology for ionosphere exploration on Mars[J]. Physics, 38 (10): 717-721(in Chinese). doi: 10.3321/j.issn:0379-4148.2009.10.004 [7] Eshleman V R. 1973. The radio occultation method for the study of planetary atmospheres[J]. Planetary and Space Science, 21(9): 1521-1531. doi: 10.1016/0032-0633(73)90059-7 [8] Fjeldbo G, Fjeldbo W C, Eshleman V R. 1966. Models for the atmosphere of Mars based on the Mariner 4 occultation experiment[J]. Journal of Geophysical Research, 71(9): 2307-2316. doi: 10.1029/JZ071i009p02307 [9] Fjeldbo G, Eshleman V R. 1968. The atmosphere of Mars analyzed by integral inversion of the Mariner IV occultation data[J]. Planetary and Space Science, 16(8): 1035-1059. doi: 10.1016/0032-0633(68)90020-2 [10] Fox J L, Weber A J. 2012. MGS electron density profiles: Analysis and modeling of peak altitudes[J]. Icarus, 221(2): 1002–1019. doi: 10.1016/j.icarus.2012.10.002 [11] 郭志忠, 符慧山, 刘杨洋. 2022. 火星空间环境中电子通量的统计研究[J]. 地球与行星物理论评, 53(4): 488-496Guo Z Z, Fu H S, Liu Y Y. 2022. Statistical study of electron flux in Martian space environment[J]. Reviews of Geophysics and Planetary Physics, 53(4): 488-496(in Chinese). [12] Hinson D P, Asmar S W, Kahan D S, et al. 2014. Initial results from radio occultation measurements with the Mars Reconnaissance Orbiter: A nocturnal mixed layer in the tropics and comparisons with polar profiles from the Mars Climate Sounder[J]. Icarus, 243: 91-103. doi: 10.1016/j.icarus.2014.09.019 [13] 胡雄, 吴小成, 宫晓艳, 等. 2009. 火星电离层无线电掩星探测仿真研究[J]. 天文学报, 50(3): 301-311 doi: 10.3321/j.issn:0001-5245.2009.03.007Hu X, Wu X C, Gong X Y, et al. 2009. Simulation of radio occultation[J]. Astronomical News, 50(3): 301-311(in Chinese). doi: 10.3321/j.issn:0001-5245.2009.03.007 [14] Hu X, Wu X, Song S, et al. 2022. First observations of Mars atmosphere and ionosphere with Tianwen-1 radio-occultation technique on 5 August 2021[J]. Remote Sensing, 14: 2718-2727. doi: 10.3390/rs14112718 [15] 焦维新, 邹鸿. 2009. 行星科学[M]. 北京: 北京大学出版社.Jiao W X, Zou H. 2009. Planetary Science[M]. Beijing: Peking University Press (in Chinese). [16] Kliore A, Cain D L, Levy G S, et al. 1965. Occultation experiment: Results of the first direct measurement of Mars’s atmosphere and ionosphere[J]. Science, 149: 1243-1248. doi: 10.1126/science.149.3689.1243 [17] Kliore A, Fjeldbo G, Seidel, B L, et al. 1969. Mariners6 and 7: Radio occultation measurements of the atmosphere of Mars[J]. Science, 166(3911): 1393-1397. doi: 10.1126/science.166.3911.1393 [18] Kliore A J, Cain D L, Fjeldbo G, et al. 1972a. Mariner 9 S-band Martian occultation experiment: Initial results on the atmosphere and topography of Mars[J]. Science, 175(4019): 313-317. doi: 10.1126/science.175.4019.313 [19] Kliore A J, Cain D L, Fjeldbo G, et al. 1972b. The atmosphere of Mars from Mariner 9 radio occultation measurements[J]. Icarus, 17(2): 484-516. doi: 10.1016/0019-1035(72)90014-0 [20] Kliore A J, Fjeldbo G, Seidel B L, et al. 1973. S band radio occultation measurements of the atmosphere and topography of Mars with Mariner 9: Extended mission coverage of polar and intermediate latitudes[J]. Journal of Geophysical Research, 78(20): 4331-4351. doi: 10.1029/JB078i020p04331 [21] Kliore A J. 1974. Radio occultation exploration of Mars[J]. Symposium - International Astronomical Union, 65: 295-316. doi: 10.1017/S0074180900025523 [22] Kliore A J. 1992. Radio Occultation Observations of the Ionospheres of Mars and Venus[M]//Luhmann J G, Tatrallyay M, Pepin R O. Geophysical Monograph Series, 265-276. [23] 乐新安, 郭英华, 曾桢, 等. 2016. 近地空间环境的GNSS无线电掩星探测技术[J]. 地球物理学报, 59(4): 1161-1188 doi: 10.6038/cjg20160401Le X A, Guo Y H, Zeng Z, et al. 2016. GNSS radio occultation detection technology in the near-Earth space environment[J]. Journal of Geophysics, 59(4): 1161-1188(in Chinese). doi: 10.6038/cjg20160401 [24] 李春来, 刘建军, 耿言, 等. 2018. 中国首次火星探测任务科学目标与有效载荷配置[J]. 深空探测学报, 5(5): 406-413 doi: 10.15982/j.issn.2095-7777.2018.05.002Li C L, Liu J J, Geng Y, et al. 2018. Scientific objectives and payload configuration of China's first Mars exploration mission[J]. Journal of Deep Space Exploration, 5(5): 406-413(in Chinese). doi: 10.15982/j.issn.2095-7777.2018.05.002 [25] 刘学富, 张燕平, 李志安, 等. 2004. 基础天文学[M]. 北京: 高等教育出版社.Liu X F, Zhang Y P, Li Z A, et al. 2004. Basic Astronomy[M]. Beijing: Higher Education Press (in Chinese). [26] Mendillo M, Narvaez C, Moore L, et al. 2022. Jupiter's enigmatic ionosphere: Electron density profiles from the Pioneer, Voyager, and Galileo radio occultation experiments[J]. Journal of Geophysical Research: Planets, 127(3): 169-193. [27] Nakamura M, Yamashita K, Yoshikawa I, et al. 1999. Helium observation in the Martian ionosphere by an X-ray ultraviolet scanner on Mars orbiter NOZOMI[J]. Earth, Planets and Space, 51(1): 61-70. [28] Pätzold M, Neubauer F M, Carone L, et al. 2004. MaRS: Mars Express Orbiter Radio Science[M]//Mars Express: The Scientific Payload. Noordwijk, Netherlands: ESA Publications Division, 141-163. [29] 秦珺峰, 邹鸿, 叶雨光. 2019. 基于无线电掩星观测的火星高层大气研究[J]. 航天器环境工程, 36(6): 571-583 doi: 10.12126/see.2019.06.007Qin J F, Zou H, Ye Y G. 2019. Mars upper atmospheric research based on radio occultation observations[J]. Spacecraft Environmental Engineering, 36(6): 571-583(in Chinese). doi: 10.12126/see.2019.06.007 [30] 仇通胜. 2021. 基于北斗三号的无线电掩星接收机信号处理关键技术研究[D]. 北京: 中国科学院大学(中国科学院国家空间科学中心).Qiu T S. 2021. Research on key technology of radio occultation receiver based on Beidou 3[D]. Beijing: University of Chinese Academy of Sciences (National Space Science Center, Chinese Academy of Sciences)(in Chinese). [31] Spinrad H, Schorn R A, Moore R, et al. 1966. High-dispersion spectroscopic observations of Mars. I. The CO2 content and surface pressure[J]. Astrophysical Journal, 146(2): 331-339. [32] Sweeney D, Ao C, Vergados P, et al. 2021. Enabling Mars radio occultation by smallsats[C]// 2021 IEEE Aerospace Conference. [33] Tan X, Liu J, Zhang X, et al. 2021. Design and validation of the scientific data products for China’s Tianwen-1 mission[J]. Space Science Reviews, 217(5): 69-90. doi: 10.1007/s11214-021-00843-6 [34] 王明远, 王美, 平劲松, 等. 2021. 月球空间环境研究进展[J]. 深空探测学报, 8(5): 486-494 doi: 10.15982/j.issn.2096-9287.2021.20200013Wang M Y, Wang M, Ping J S, et al. 2021. Research progress on lunar space environment[J]. Journal of Deep Space Exploration, 8(5): 486-494(in Chinese). doi: 10.15982/j.issn.2096-9287.2021.20200013 [35] 王帅, 张扬眉. 2016. "火星生物学-2016" 奔向火星[J]. 国际太空, 4: 30-36Wang S, Zhang Y M. 2016. "Mars Biology-2016" headed to Mars[J]. International Space, 4: 30-36(in Chinese). [36] 王帅. 2020. 阿联酋首个火星探测任务分析[J]. 国际太空, 8: 37-42 doi: 10.3969/j.issn.1009-2366.2020.03.008Wang S. 2020. Analysis of the UAE's first Mars exploration mission[J]. International Space, 8: 37-42(in Chinese). doi: 10.3969/j.issn.1009-2366.2020.03.008 [37] Withers P, Smith M. 2006. Atmospheric entry profiles from the Mars Exploration Rovers Spirit and Opportunity[J]. Icarus, 185(1): 133-142. doi: 10.1016/j.icarus.2006.06.013 [38] Withers P, Weiner S, Ferreri N R. 2015. Recovery and validation of Mars ionospheric electron density profiles from Mariner 9[J]. Earth, Planets and Space, 67(1): 194-205. [39] Withers P, Felici M, Flynn C. 2020a. Recovery and validation of Mars ionospheric electron density profiles from Viking orbiter radio occultation observations[J]. Planet and Science, 1(1): 1-14. [40] Withers P, Felici M, Mendillo M, et al. 2020b. The MAVEN radio occultation science experiment (ROSE)[J]. Space Science Reviews, 216(4): 61-109. doi: 10.1007/s11214-020-00687-6 [41] Withers P, Hensley K, Vogt M F, et al. 2020c. Recovery and validation of Venus ionospheric electron density profiles from Pioneer Venus Orbiter radio occultation observations[J]. The Planetary Science Journal, 1(3): 78-90. doi: 10.3847/PSJ/abcaf9 [42] Withers P, Hensley K, Vogt M F, et al. 2020d. Recovery and validation of Venus neutral atmospheric profiles from Pioneer Venus Orbiter radio occultation observations[J]. The Planetary Science Journal, 1(3): 79-93. doi: 10.3847/PSJ/abc476 [43] Withers P, Moore L. 2020. How to process radio occultation data: 2. From time series of two-way, single-frequency frequency residuals to vertical profiles of ionospheric properties[J]. Radio Science, 55(8): 46-70. [44] Withers P, Felici M, Hensley K, et al. 2021. The ionosphere of Mars from solar minimum to solar maximum: Dayside electron densities from MAVEN and Mars Global Surveyor radio occultations[J]. Icarus, 393(4): 508-517. [45] 吴小成. 2008. 电离层无线电掩星技术研究[D]. 北京: 中国科学院研究生院(空间科学与应用研究中心).Wu X C. 2008. Research on ionospheric radio occultation technology[D]. Beijing: The Graduate School of the Chinese Academy of Sciences (Center for Space Science and Applied Research) (in Chinese). [46] Zhang A B, Kong L G, Li W Y, et al. 2022. Tianwen-1 MINPA observations in the solar wind[J]. Earth and Planetary Physics, 6(1): 1-9. doi: 10.26464/epp2022014 [47] Zhang M H G, Luhmann J G, Kliore A J, et al. 1990. A post-Pioneer Venus reassessment of the Martian dayside ionosphere as observed by radio occultation methods[J]. Journal of Geophysical Research, 95(B9): 14829-14839. doi: 10.1029/JB095iB09p14829 [48] 张素君, 平劲松, 洪振杰, 等. 2009. 星-地无线电掩星技术探测火星大气和电离层[J]. 物理, 38(10): 722-728 doi: 10.3321/j.issn:0379-4148.2009.10.005Zhang S J, Ping J S, Hong Z J, et al. 2009. Star-Earth radio occultation technology probes the Martian atmosphere and ionosphere[J]. Physics, 38 (10): 722-728(in Chinese). doi: 10.3321/j.issn:0379-4148.2009.10.005 [49] 张素君, 王明远, 简念川, 等. 2013. 基于无线电掩星观测的火星电离层观测研究进展[J]. 中国科学: 物理学 力学 天文学, 43: 903-916 doi: 10.1360/132012-920Zhang S J, Wang M Y, Jian N C, et al. 2013. A review on the study of Martian ionosphere based on Radio Occultation observations[J]. Sci Sin-Phys Mech Astron, 43: 903-916(in Chinese). doi: 10.1360/132012-920 [50] Zhang S J, Cui J, Guo P, et al. 2015. Martian electron density profiles retrieved from Mars Express dual-frequency radio occultation measurements[J]. Advances in Space Research, 55(9): 2177-2189. doi: 10.1016/j.asr.2015.01.030 [51] 张扬眉. 2013. 印度成功发射火星轨道器[J]. 国际太空, 12: 52-58Zhang Y M. 2013. India successfully launches the Mars orbiter [J]. International Space, (12): 52-58(in Chinese). [52] 张扬眉. 2020. 世界火星探测一览表[J]. 国际太空, 8: 49-50 doi: 10.3969/j.issn.1009-2366.2020.06.012Zhang Y M. 2020. World Mars exploration list [J]. International Space, 8: 49-50(in Chinese). doi: 10.3969/j.issn.1009-2366.2020.06.012 [53] 张志华, 王鑫, 吕达仁. 2022. LEO-LEO 微波掩星探测温度和水汽廓线研究进展[J]. 遥测遥控, 43(1): 1-12.Zhang Z H, Wang X, Lü D R. 2022. Progress of temperature and water vapor profiles detected by LEO-LEO microwave occultation[J]. Journal of Telemetry, Tracking and Command, 43(1): 1-12(in Chinese). [54] 邹鸿, 陈鸿飞, 施伟红, 等. 2011. 火星电离层探测[J]. 空间科学学报, 31(3): 323-329 doi: 10.11728/cjss2011.03.323Zou H, Chen H F, Shi W H, et al. 2011. Mars ionosphere exploration[J]. Journal of Space Science, 31(3): 323-329(in Chinese). doi: 10.11728/cjss2011.03.323 -