Chinese Science Bulletin, Volume 65 , Issue 14 : 1297-1304(2020) https://doi.org/10.1360/TB-2019-0805

Life in the near space and implications for astrobiology

Wei Lin 1,2,*
More info
  • ReceivedDec 9, 2019
  • AcceptedMar 25, 2020
  • PublishedApr 8, 2020


Near space is a region that lies between 20 and 100 km above sea level, which includes the major region of the stratosphere, the mesosphere and the lower thermosphere. Near space comprises a harsher physical environment which contains high ultraviolet light levels, subzero temperatures, desiccation and low atmospheric pressure, in comparison to the low-altitude atmosphere. This provides a unique analogue environment that resembles the surface conditions of Mars, the high-altitude atmospheric environments of Venus and the high radiation environments of early Earth. Microorganisms can enter the lower atmosphere and the near space through weather systems like wind, geological activities like earthquake and volcanic eruption and human activities like air transportation. In recent years, methodological and technological advances have deepened our understanding of the diversity and survival strategies of organisms in near space. Payload systems and methods for exposing organisms and for in situ collecting microbial samples in near space have been designed and developed. Consequently, a growing number of studies investigate the microbial survival strategies in near space by exposing model microorganisms (e.g., bacteria, archaea and yeasts) to near space extreme environments through flight exposures. A diverse group of microorganisms have been isolated, identified and characterized from near space, suggesting that it may potentially contain a vast unknown microbial biosphere. The dispersal of life in near space may play an essential role in shaping global patterns of microbial biodiversity and biogeography. The ability of these microbes to survive under near space extreme environments has prompted researchers from different disciplines to study them to better understand their diversity, distribution and survival strategies. Near space not only provides great opportunities to investigate some basic biological questions such as the biological effects of radiations, but it also has a wide application potential since microorganisms in near space, as extremophiles, are a valuable source of a variety of new genes and enzymes. Astrobiology is the study of the origin, evolution, habitability and future of life on Earth and beyond in the context of cosmic evolution. One promising research field in astrobiology is planetary analogue research which conducts experiments and tests in specific environments on Earth that have physical/chemical similarities to the extraterrestrial environments. Analogue research has offered new insights into the planetary habitability and the search for extraterrestrial life. Near space as a natural laboratory can provide hard evidence for important astrobiology topics including the limits to life on Earth, the upper boundary of Earth’s biosphere, the possibility of interplanetary transport of life, the assessment of panspermia hypothesis and the planetary protection. With the recent development of the Chinese Space Station and deep-space exploration, the study of near space biology will provide support for future space station related research and will further promote the development of astrobiology in China. Here I review the major advances in biodiversity in near space and their survival strategies, with emphases on key astrobiology questions associated with the research of near space. I also highlight major challenges that will be necessary to address in future research and discuss possible perspectives in the study of near space biology.

Funded by



感谢中国科学院水生生物研究所王高鸿研究员和中国科学院地质与地球物理研究所田兰香副研究员对文章初稿提出的意见; 感谢中国科学院地质与地球物理研究所潘永信院士在研究过程中给予的建议和指导; 感谢“鸿鹄专项”HH-19-2和HH-19-9飞行实验全体参研人员.


[1] Huang W N, Zhang X J, Li Z B, et al. Development status and application prospect of near space science and technology (in Chinese). Sci Technol Rev, 2019, 37: 46–62 [黄宛宁, 张晓军, 李智斌, 等. 临近空间科学技术的发展现状及应用前景. 科技导报, 2019, 37: 46–62]. Google Scholar

[2] Griffin D W, Gonzalez-Martin C, Hoose C, et al. Global-scale atmospheric dispersion of microorganisms. In: Delort A M, Amato P, eds. Microbiology of Aerosols. Hoboken: John Wiley & Sons, 2017. 155–194. Google Scholar

[3] DasSarma P, DasSarma S. Survival of microbes in Earth’s stratosphere. Curr Opin Microbiol, 2018, 43: 24-30 CrossRef PubMed Google Scholar

[4] Joly M, Attard E, Sancelme M, et al. Ice nucleation activity of bacteria isolated from cloud water. Atmos Environ, 2013, 70: 392-400 CrossRef Google Scholar

[5] Polymenakou P N. Atmosphere: A source of pathogenic or beneficial microbes? Atmosphere, 2012, 3: 87–102. Google Scholar

[6] Griffin D W. Atmospheric movement of microorganisms in clouds of desert dust and implications for human health. Clin Microbiol Rev, 2007, 20: 459-477 CrossRef PubMed Google Scholar

[7] Smith D J. Microbes in the upper atmosphere and unique opportunities for astrobiology research. Astrobiology, 2013, 13: 981-990 CrossRef PubMed Google Scholar

[8] Tiquia S M, Mormile M R. Extremophiles—A source of innovation for industrial and environmental applications. Environ Technol, 2010, 31: 823 CrossRef PubMed Google Scholar

[9] Meriwether J W. Mesosphere inversion layers and stratosphere temperature enhancements. Rev Geophys, 2004, 42: RG3003. Google Scholar

[10] Khodadad C L, Wong G M, James L M, et al. Stratosphere conditions inactivate bacterial endospores from a Mars spacecraft assembly facility. Astrobiology, 2017, 17: 337-350 CrossRef PubMed Google Scholar

[11] Smith D J, Thakrar P J, Bharrat A E, et al. A balloon-based payload for Exposing Microorganisms in the Stratosphere (E-MIST). Gravit Space Res, 2014, 2: 70–80. Google Scholar

[12] Bryan N C, Stewart M, Granger D, et al. A method for sampling microbial aerosols using high altitude balloons. J Microbiol Methods, 2014, 107: 161-168 CrossRef PubMed Google Scholar

[13] Della Corte V, Rietmeijer F J M, Rotundi A, et al. Introducing a new stratospheric dust-collecting system with potential use for upper atmospheric microbiology investigations. Astrobiology, 2014, 14: 694-705 CrossRef PubMed Google Scholar

[14] Griffin D W. Terrestrial microorganisms at an altitude of 20000 m in Earth’s atmosphere. Aerobiologia, 2004, 20: 135-140 CrossRef Google Scholar

[15] Griffin D W. Non-spore forming eubacteria isolated at an altitude of 20000 m in Earth’s atmosphere: Extended incubation periods needed for culture-based assays. Aerobiologia, 2008, 24: 19-25 CrossRef Google Scholar

[16] Smith D J, Griffin D W, Schuerger A C. Stratospheric microbiology at 20 km over the Pacific Ocean. Aerobiologia, 2010, 26: 35-46 CrossRef Google Scholar

[17] Imshenetsky A A, Lysenko S V, Kazakov G A. Upper boundary of the biosphere. Appl Environ Microbiol, 1978, 35: 1-5 CrossRef Google Scholar

[18] Greene V W. Microbiological exploration of stratosphere: Results of six experimental flights. In: Proceedings of the Atmospheric Biology Conference. Washington DC: National Aeronautics and Space Administration, 1965. 199–211. Google Scholar

[19] Soffen G A. Atmospheric collection at 130000 feet. In: Proceedings of the Atmospheric Biology Conference. Washington DC: National Aeronautics and Space Administration, 1965. 213–219. Google Scholar

[20] Narlikar J V, Lloyd D, Wickramasinghe N C, et al. A balloon experiment to detect microorganisms in the outer space. Astrophys Space Sci, 2003, 285: 555-562 CrossRef Google Scholar

[21] Wainwright M, Wickramasinghe N C, Narlikar J V, et al. Microorganisms cultured from stratospheric air samples obtained at 41 km. FEMS Microbiol Lett, 2003, 218: 161-165 CrossRef PubMed Google Scholar

[22] Rauf K, Hann A, Wallis M, et al. Study of putative microfossils in space dust from the stratosphere. Int J Astrobiol, 2010, 9: 183-189 CrossRef Google Scholar

[23] Shivaji S, Chaturvedi P, Suresh K, et al. Bacillus aerius sp. nov., Bacillus aerophilus sp. nov., Bacillus stratosphericus sp. nov. and Bacillus altitudinis sp. nov., isolated from cryogenic tubes used for collecting air samples from high altitudes. Int J Syst Evol Microbiol, 2006, 56: 1465-1473 CrossRef PubMed Google Scholar

[24] Shivaji S, Chaturvedi P, Begum Z, et al. Janibacter hoylei sp. nov., Bacillus isronensis sp. nov. and Bacillus aryabhattai sp. nov., isolated from cryotubes used for collecting air from the upper atmosphere. Int J Syst Evol Microbiol, 2009, 59: 2977-2986 CrossRef PubMed Google Scholar

[25] Narlikar J V, Ramadurai S, Bhargava P, et al. Search for living cells in stratospheric samples. In: Hoover R B, ed. Instruments, Methods, and Missions for Astrobiology. Washington DC: International Society for Optics and Photonics, 1998, 3441. 301−305. Google Scholar

[26] Yang Y, Yokobori S, Kawaguchi J, et al. Investigation of cultivable microorganisms in the stratosphere collected by using a balloon in 2005. In: JAXA Research and Development Report: Research Reports on High Altitude Balloons, JAXA-RR-08-001. Tokyo: Japan Aerospace Exploration Agency, 2008. 35–42. Google Scholar

[27] Yang Y, Itoh T, Yokobori S I, et al. Deinococcus aetherius sp. nov., isolated from the stratosphere. Int J Syst Evol Microbiol, 2010, 60: 776-779 CrossRef PubMed Google Scholar

[28] Smith D J, Griffin D W, McPeters R D, et al. Microbial survival in the stratosphere and implications for global dispersal. Aerobiologia, 2011, 27: 319-332 CrossRef Google Scholar

[29] Tirumalai M R, Rastogi R, Zamani N, et al. Candidate genes that may be responsible for the unusual resistances exhibited by Bacillus pumilus SAFR-032 spores. PLoS One, 2013, 8: e66012 CrossRef PubMed Google Scholar

[30] DasSarma P, Laye V J, Harvey J, et al. Survival of halophilic Archaea in Earth’s cold stratosphere. Int J Astrobiol, 2017, 16: 321-327 CrossRef Google Scholar

[31] Lin W, Li Y L, Wang G H, et al. Overview and perspectives of Astrobiology (in Chinese). Chin Sci Bull, 2020, 65: 380-391 CrossRef Google Scholar

[32] Smith D J, Sowa M B. Ballooning for biologists: Mission essentials for flying life science experiments to near space on NASA large scientific balloons. Gravit Space Res, 2017, 5: 52–73. Google Scholar

[33] Sokol J. UV light could easily kill microbial stowaways to Mars. Science, 2017, : doi: 10.1126/science.aal0975 CrossRef Google Scholar

[34] Sagdeev R Z, Linkin V M, Blamont J E, et al. The VEGA Venus balloon experiment. Science, 1986, 231: 1407-1408 CrossRef PubMed Google Scholar

[35] Limaye S S, Mogul R, Smith D J, et al. Venus’ spectral signatures and the potential for life in the clouds. Astrobiology, 2018, 18: 1181-1198 CrossRef PubMed Google Scholar

[36] Wesson P S. Panspermia, past and present: Astrophysical and biophysical conditions for the dissemination of life in space. Space Sci Rev, 2010, 156: 239-252 CrossRef Google Scholar

[37] Brownlee D E. The origin and properties of dust impacting the Earth. In: Accretion of Extraterrestrial Matter Throughout Earth’s History. Boston: Springer, 2001. 1–12. Google Scholar

[38] Yang Y, Yokobori S, Yamagishi A. Assessing panspermia hypothesis by microorganisms collected from the high altitude atmosphere. Biol Sci Space, 2009, 23: 151-163 CrossRef Google Scholar

[39] Arihara K, Itoh M. UV-induced Lactobacillus gasseri mutants resisting sodium chloride and sodium nitrite for meat fermentation. Int J Food Microbiol, 2000, 56: 227-230 CrossRef Google Scholar

[40] Boto L. Horizontal gene transfer in evolution: Facts and challenges. Proc R Soc B, 2010, 277: 819-827 CrossRef PubMed Google Scholar

[41] Horneck G, Klaus D M, Mancinelli R L. Space microbiology. Microbiol Mol Biol Rev, 2010, 74: 121-156 CrossRef PubMed Google Scholar

[42] Zhou J P. Chinese space station project overall vision (in Chinese). Manned Spacefl, 2013, 19: 1–10 [周建平. 我国空间站工程总体构想. 载人航天, 2013, 19: 1–10]. Google Scholar

[43] Ye P J, Zou L Y, Wang D Y, et al. Development and prospect of Chinese deep space exploration (in Chinese). Space Int, 2018, 10: 4–10 [叶培建, 邹乐洋, 王大轶, 等. 中国深空探测领域的发展及展望. 国际太空, 2018, 10: 4–10]. Google Scholar

  • Figure 1

    Schematic representation of the cycle of microorganisms in the lower atmosphere and the near space. Near space is a region between 20 and 100 km above sea level. It lies above the troposphere (from ground level to about 8−15 km) and includes the major region of the stratosphere (from the tropopause to about 50 km above sea level), the entire mesosphere (from about 50 to 85 km above sea level) and the lower thermosphere (from about 85 to 500 km above sea level)

  • Figure 2

    The balloon-based biology exposure payload developed under the Scientific Experiment System in Near Space (SENSE) Program in the near space environment over Qinghai Province, China (~32 km above sea level)

Copyright 2020  CHINA SCIENCE PUBLISHING & MEDIA LTD.  中国科技出版传媒股份有限公司  版权所有

京ICP备14028887号-23       京公网安备11010102003388号