Radiation problems in manned spaceflight with a view towards the Space Station.

With the advent of a permanently manned Space Station, the longstanding problems of radiation protection in manned spaceflight have acquired an immediacy. This paper endeavors to emphasize the gaps of our knowledge which must be closed for effective radiation protection. The information that is required includes the accurate determination of the exposure inside the space station to the various components of the ionizing radiation, the evaluation of the biological importance of the different radiation qualities and the depth-dose distribution of the less penetrating component. There is also the possibility of an interaction with weightlessness. It is necessary to establish adequate radiation protection standards and a system of dosimetric surveillance. There is a need for studies of methods on the possibilities of hardening selective shielding of the space station. Spaceflight experiments, which might contribute to the solution of some of these problems are discussed.     

Radiation protective structures on the base of a case study for a manned Mars mission

Plans for interplanetary manned space missions imply significant risks arising from human's exposure to the hostile space environment. Thus the design of reliable protection systems against the ionizing cosmic radiation becomes one of the most relevant issues. In this paper the composition and magnitude of the atmospheric radiation on the planetary surface and for typical interplanetary transfer configurations have been analyzed. The investigation based on prior NASA and ESA mission results, using a manned mission to planet Mars as a case study. According to this, the time-dependent character of the consistency of cosmic radiation has been taken into account, which is justified by the interdependence of the radiation magnitude to the solar cycle. With regard to this paper it implies even solar particle events. The results have been compared to the protective character of different materials potentially usable as a habitat's structural shell and for interplanetary spacecrafts. The investigation aimed on particle energy degradation rates and reduction of secondary particle production. In this regard the physical process of absorbing effectiveness against particle radiation has been examined by analytical calculation and given scientific results, depending on thickness and molecular composition of the materials. The most suitable materials have been used for shield design proposals using different configurations, evaluating the use of aluminium, water tanks and polyethylene bricks.     

面向载人月球探测的月面环境模拟试验关键技术分析

文章针对未来有人参与的月球探测任务,首先开展了月球表面环境地面模拟试验验证需求分析,归纳总结了国内外技术发展现状。然后,提出并分析了载人月球探测地面模拟试验需重点研究的关键技术:真空热环境下月面移动式多体低重力模拟技术;复杂月面环境高精度热流模拟技术;大容量布尘条件下超高真空获得与保持技术;月面辐射与月尘环境模拟技术;月尘防护效能量化评估技术;月面综合环境试验验证技术等。最后,给出了面向载人月球探测的月面环境模拟试验技术研究总体方案,并对月面环境模拟试验技术的发展目标进行了展望。     

Analytical definition and proposed concept for the manned infrastructure of a lunar outpost

A recent study made by ESA has reviewed the scientific investigations to be only, or best, performed on the Moon (Return to the Moon, ESA SP-1150, June 1992), and has identified the need for a manned lunar outpost to provide support to field geologists in sampling and in-situ observations of the lunar surface, and to allow the refurbishments of surface stations and rovers. Planning and development for a manned outpost on the Moon requires an in-depth understanding and analysis of the functions this outpost is expected to perform. We therefore analyzed the impact of the proposed scientific investigations on the design of a manned lunar outpost. The specific questions raised in our study were: What are the medical, physiological and psychological risks for a crew to stay and to work on the Moon? What transit and lunar surface infrastructures (habitats and vehicles) are needed to minimize those risks?     

模拟载人探月中航天员空间辐射风险评估

空间辐射是长期载人航天飞行任务中影响航天员健康的重要风险因素。为了探求载人探月过程中对空间辐射的合理防护方式,文章借助空间辐射场模型对"嫦娥三号"飞行任务在不同质量厚度材料屏蔽下的舱内空间辐射环境进行了仿真计算,并确定了航天员各器官接受的空间辐射剂量、剂量当量以及有效剂量等辐射防护量以进行辐射风险评估。结果表明,随着屏蔽厚度的增加,航天员的各组织或器官的吸收剂量和剂量当量以及有效剂量均明显降低;采用质量屏蔽的方法对低于100 Me V的质子具有很好的防护效果,但对高能质子或重离子的防护效果不明显。计算和分析显示,载人探月过程中,只要采取适当的防护措施,航天员的空间辐射风险是可控的。     

载人航天器空间碎片防护与减缓设计

为降低空间碎片撞击所带来的威胁,文章针对某载人航天器进行了空间碎片撞击风险分析,并设计了空间碎片专用防护结构,制定了轨道规避策略;同时针对重点设备进行钝化设计,并采用寿命末期有控离轨制动方案。以上措施可有效实现空间碎片减缓。     

On the problem of lunar radiation environment

In connection with projects of manned bases on the Moon it becomes topical to estimate radiation danger for their inhabitants. In this paper we describe a method of evaluation of the radiation environment on the lunar surface produced by galactic and solar cosmic rays. The roles of both primary and secondary radiations generated in the depth of the lunar soil under the action of high-energy protons and nuclei are taken into account. Calculated fluxes of particles are used in order to estimate annual averaged absorbed and equivalent local dose rates in tissues. It is established that in the lunar rock the contribution of secondary neutrons to the dose rate exceeds that of protons. The contribution of the secondary particles generated by nuclei of galactic cosmic rays to the dose rate is estimated.     

火星载人探测中辐射防护综述

火星探测是人类太空探索的重要组成部分,火星载人探测中航天员的辐射安全问题是人们最为关心的问题。文章扼要介绍了美国/俄罗斯火星载人探测技术的发展过程,重点阐述了探测中的辐射环境、辐射效应以及国外探测结果;在此基础上,对火星探测中的辐射剂量进行了预示,提出了辐射防护建议。     

载人航天器密封舱内生物剂量三维仿真技术

对载人航天器密封舱内航天员遭受的生物剂量进行研究分析,可为乘员辐射防护设计和工程实施提供依据。文章将基于一维深度-剂量计算、结合扇区射线法的三维辐射仿真技术运用于载人航天器总体设计中,以某中期驻留载人航天器为例,构建生物剂量仿真分析模型。计算实例分析表明,三维剂量仿真结果可有效指导乘员辐射防护优化设计,对后续长期载人飞行中的航天员辐射安全设计具有较强的实用性。     

载人航天器舱内辐射剂量监测技术综述

文章介绍了美国、苏联/俄罗斯载人航天器舱内辐射剂量监测技术及部分监测结果,分析了我国“神舟3号”和“神舟4号”飞船返回舱内的辐射剂量探测技术及结果,并在此基础上就我国载人航天器的辐射剂量探测方法提出若干建议。     

载人航天器密封舱流动和传热数值模型及其地面验证

为求解载人航天器密封舱内复杂的空气对流、导热和辐射三者耦合的传热问题,本文建立了载人航天器密封舱的流动与传热数值模型,对地面试验状态下密封舱内的空气流动与传热进行了仿真分析,并利用试验结果对数值模型进行了验证.结果表明,建立的数值模型可靠且具有较高精度,仿真结果与地面试验数据吻合性较好,可进一步用于热控系统性能评估、在轨支持和故障处理.     

航天器内环境模拟技术

在载人航天中,航天员的辐射危险性是必须受到重视的问题。航天器的内环境是一个复杂的复合场,受外部辐射场和屏蔽材料等多种因素的影响,单一的探测技术很难探测得到内部辐射场的性质特点,而且无法对辐射危害进行评估。文章从射线与物质相互作用的角度出发,对NASA所用航天器内环境的模拟技术进行了介绍,并介绍了根据我国国情已往开展的相关研究工作,包括在Geant4软件包的基础上,将射线与物质相互作用的处理方法进行扩展,开发新的软件,编制SRP(Space Radiation Protection)程序等。     

一种综合式载人月球基地总体方案及建造规划设想

构建载人月球基地是实现对月球资源深度开发和利用的重要手段之一,文章提出了刚性舱、刚性＋柔性结构以及建造式等三种典型结构的载人月球基地方案,并对三种典型方案的优缺点进行对比分析,在此基础上提出了一种综合式载人月球基地方案设想,基地内部主体创新性地采用充气式柔性连接的方式,外部主体包括月壤防护层、植物密封舱和应急救生飞船,活动系统包括月球车和月球机器人。围绕该方案并结合文章提出的载人月球基地主要技术指标,并对载人月球基地选址、结构设计和构建、空间辐射防护、热管理、能源、通信与导航、生命保障和应急救生技术等关键技术方案进行了分析,为中国未来建设载人月球基地提供了参考。     

空间高能质子对航天器材料损伤的仿真分析

近地空间是各种载人飞船、应用卫星、空间站的主要活动区域,区域内存在大量由地磁场捕获的高能带电粒子,严重影响航天器和航天员的安全。为此,需要对内辐射带低高度空间的高能带电粒子环境及其通量分布进行研究。如何对质子进行有效屏蔽对空间辐射防护有重要的研究意义。文章针对粒子在空间环境中的辐射,简要介绍了质子在空间环境中的分布情况及在物质中的传输问题。利用SRIM软件模拟质子在不同材料(铝、聚乙烯)中输运过程。根据得到的射程与能量关系及对阻止本领的分析,从理论上提出航天器防护的合理方案。     

载人航天器密封舱内除湿研究

为保证航天员在轨生活健康,避免密封舱内结露,对载人航天器密封舱内空气除湿进行了理论研究:针对载人航天器地面封舱前干空气置换,建立了相对湿度估算模型;对航天器在轨采用冷凝干燥装置主动除湿进行了研究,建立了密封舱内空气湿度平衡方程,推导出冷凝干燥风机风量估算模型。相对湿度估算模型及风机风量估算模型可为实际工程设计提供参考。     

The Second Stage of BTN Neutron Space Experiment onboard the Russian Section of the International Space Station: the BTN-M2 Instrument

Cosmic Research - As recent studies onboard various spacecraft have shown, one unresolved technical problem of manned interplanetary flights at the moment is the high radiation background of...     

载人航天器密封舱微生物防控技术体系框架研究概述

载人航天器密封舱内环境适宜航天员工作和生活,同时也给空间微生物提供了生长繁殖的有利条件。而空间微重力和电磁辐射等环境会加大空间微生物对材料的腐蚀能力。因此,必须对空间微生物防控技术进行体系化研究。文章从空间微生物菌种的采集和鉴定、空间环境下微生物对航天材料的腐蚀机理、载人航天材料抗菌涂层选择以及微生物控制技术等方面对微生物防控体系进行阐述,可以作为开展载人航天器空间微生物防控技术研究的参考。     

Assessment of the radiation environment on the Moon

In connection with projects on a manned base on the Moon, the assessment of radiation risk to staff of the base owing to galactic (GCR) and solar (SEP) cosmic radiation becomes very relevant. The paper describes the methodology for assessing the radiation environment on the lunar surface and in the depths of lunar soil taking into account the primary and secondary radiation caused by protons and nuclei of GCR and SEP. Calculated fluencies of particles are used to estimate the average annual absorbed and equivalent local doses in tissue. Contribution to the dose of secondary neutrons at depths of lunar soil exceeds the contribution of protons. Contribution to the dose of secondary particles generated by GCR nuclei should be taken into account.     

Probabilistic assessment of radiation risk for astronauts in space missions

Accurate estimations of the health risks to astronauts due to space radiation exposure are necessary for future lunar and Mars missions. Space radiation consists of solar particle events (SPEs), comprised largely of medium energy protons (less than several hundred MeV); and galactic cosmic rays (GCR), which include high-energy protons and heavy ions. While the frequency distribution of SPEs depends strongly upon the phase within the solar activity cycle, the individual SPE occurrences themselves are random in nature. A solar modulation model has been developed for the temporal characterization of the GCR environment, which is represented by the deceleration potential, ?. The risk of radiation exposure to astronauts as well as to hardware from SPEs during extra-vehicular activities (EVAs) or in lightly shielded vehicles is a major concern for radiation protection. To support the probabilistic risk assessment for EVAs, which could be up to 15% of crew time² on lunar missions, we estimated the probability of SPE occurrence as a function of solar cycle phase using a non-homogeneous Poisson model [1] to fit the historical database of measurements of protons with energy>30 MeV, Φ₃₀. The resultant organ doses and dose equivalents, as well as effective whole body doses, for acute and cancer risk estimations are analyzed for a conceptual habitat module and for a lunar rover during space missions of defined durations. This probabilistic approach to radiation risk assessment from SPE and GCR is in support of mission design and operational planning for future manned space exploration missions.     

载人月面着陆与上升飞行器辐射环境适应性研究

载人月面着陆与上升飞行器是在载人月球探测任务中用于月球轨道与月面之间人员、货物往返的运输工具。针对载人月面着陆与上升飞行器全寿命周期内的辐射环境进行了分析,对近地轨道、地月转移及环月轨道的辐射环境中的高能带电粒子能谱进行了对比,对其辐射环境适应性进行了评估,提出了针对性的辐射防护建议,供月面着陆与上升飞行器设计参考。