Mars Phobos and Deimos Survey (M-PADS) – A martian Moons orbiter and Phobos lander

We describe a Mars ‘Micro Mission’ for detailed study of the martian satellites Phobos and Deimos. The mission involves two ∼330 kg spacecraft equipped with solar electric propulsion to reach Mars orbit. The two spacecraft are stacked for launch: an orbiter for remote investigation of the moons and in situ studies of their environment in Mars orbit, and another carrying a lander for in situ measurements on the surface of Phobos (or alternatively Deimos). Phobos and Deimos remain only partially studied, and Deimos less well than Phobos. Mars has almost always been the primary mission objective, while the more dedicated Phobos project (1988–89) failed to realise its full potential. Many questions remain concerning the moons’ origins, evolution, physical nature and composition. Current missions, such as Mars Express, are extending our knowledge of Phobos in some areas but largely neglect Deimos. The objectives of M-PADS focus on: origins and evolution, interactions with Mars, volatiles and interiors, surface features, and differences. The consequent measurement requirements imply both landed and remote sensing payloads. M-PADS is expected to accommodate a 60 kg orbital payload and a 16 kg lander payload. M-PADS resulted from a BNSC-funded study carried out in 2003 to define candidate Mars Micro Mission concepts for ESA’s Aurora programme.     

Investigation of the Mars Express HRSC color channel calibration

The High Resolution Stereo Camera (HRSC) onboard the Mars Express spacecraft in orbit about Mars has four detector channels dedicated to produce images in four spectral channels. Utilizing these spectrophotometric data requires understanding the instrument radiometric calibration and other photometric properties of the data. We present here some results of our investigation into the HRSC color data characteristics. This covers comparison of HRSC measurements with those of telescopes and the Observatoire pour la Minéralogie, l’Eau, les Glaces et l’Activité (OMEGA) instrument, also on Mars Express. We also investigate the dependence of HRSC Color measurements on solar phase angle and altitude of the Mars surface. These results confirm and extend our earlier findings [McCord, T.B., Adams, J.B., Bellucci, G., Combe, J.-Ph., Hansen, G., Hoffman, H., Jaumann, R., Lumme, K., Neukum, G., Pinet, P., Poulet, F., the HRSC Co-I Team, The Mars Express high Resolution Stereo Camera spectrophotometric data: characteristics and science analysis. J. Geophys. Res. 112, E6, 2007.]. A basic finding from our study is that there are nearly constant offsets between the I/F value derived from the HRSC data and those determined from OMEGA and groundbased telescope measurements, especially in the HRSC red bandpass. These offsets are nearly independent of solar phase angle and Mars surface altitude but are considerably larger for the one comparison at Phobos we were able to make. Several hypotheses could explain these effects: atmospheric scattering, surface photometric effects, shift of the spatial registration or calibration. All these possibilities were investigated.     

Phobos regolith simulants PGI-1 and PCA-1

The Martian moon Phobos is the target of the upcoming JAXA Martian Moons eXploration (MMX) mission. There are currently no known samples of Phobos, so spacecraft hardware testing and scientific studies require Phobos regolith simulants. Here, we present two new Phobos regolith simulants: Phobos Captured Asteroid-1 (PCA-1) and Phobos Giant Impact (PGI-1). These two simulants reflect the two hypotheses for Phobos’s formation, and thus the two broad possibilities for composition. This work follows previous efforts to document the development of mineralogically accurate simulants, in an effort to overcome past pitfalls with inappropriate uses of simulants. We report physical and geotechnical properties of PCA-1 and PGI-1, including their reflectance spectra, grain size distributions, abrasivity, cohesion, strength, and hardness. Our intent is for PCA-1 and PGI-1 to be open standards for Phobos simulants, and we present the simulant recipes and production methodology for use and modification by the community.     

Four-month Moon and Mars crew water utilization study conducted at the Flashline Mars Arctic Research Station,Devon Island,Nunavut

A categorized water usage study was undertaken at the Flashline Mars Arctic Research Station on Devon Island, Nunavut in the High Canadian Arctic. This study was conducted as part of a long duration four-month Mars mission simulation during the summer of 2007. The study determined that the crew of seven averaged 82.07 L/day over the expedition (standard deviation 22.58 L/day). The study also incorporated a Mars Time Study phase which determined that an average of 12.12 L/sol of water was required for each crewmember. Drinking, food preparation, hand/face, oral, dish wash, clothes wash, shower, shaving, cleaning, engineering, science, plant growth and medical water were each individually monitored throughout the detailed study phases. It was determined that implementing the monitoring program itself resulted in an approximate water savings of 1.5 L/day per crewmember. The seven person crew averaged 202 distinct water draws a day (standard deviation 34) with high water use periods focusing around meal times. No statistically significant correlation was established between total water use and EVA or exercise duration. Study results suggest that current crew water utilization estimates for long duration planetary surface stays are more than two times greater than that required.     

The MAGO experiment for dust environment monitoring on the Martian surface

Among the main directions identified for future Martian exploration, the study of the properties of dust dispersed in the atmosphere, its cycle and the impact on climate are considered of primary relevance. Dust storms, dust devils and the dust “cycle” have been identified and studied by past remote and in situ experiments, but little quantitative information is available on these processes, so far. The airborne dust contributes to the determination of the dynamic and thermodynamic evolution of the atmosphere, including the large-scale circulation processes and its impact on the climate of Mars. Moreover, aeolian erosion, redistribution of dust on the surface and weathering processes are mostly known only qualitatively. In order to improve our knowledge of the airborne dust evolution and other atmospheric processes, it is mandatory to measure the amount, mass-size distribution and dynamical properties of solid particles in the Martian atmosphere as a function of time. In this context, there is clearly a need for the implementation of experiments dedicated to study directly atmospheric dust. The Martian atmospheric grain observer (MAGO) experiment is aimed at providing direct quantitative measurements of mass and size distributions of dust particles, a goal that has never been fully achieved so far. The instrument design combines three types of sensors to monitor in situ the dust mass flux (micro balance system, MBS) and single grain properties (grain detection system, GDS + impact sensor, IS). Technical solutions and science capabilities are discussed in this paper.     

KuaFu Mission

The KuaFu mission-Space Storms, Aurora and Space Weather Explorer-is an "L1+Polar" triple satellite project composed of three spacecraft: KuaFu-A will be located at L1 and have instruments to observe solar EUV and FUV emissions, and white-light Coronal Mass Ejections (CMEs), and to measure radio waves, the local plasma and magnetic field,and high-energy particles. KuaFuB1 and KuaFu- B2 will bein polar orbits chosen to facilitate continuous 24 hours a day observation of the north polar Aurora Oval. The KuaFu mission is designed to observe the complete chain of disturbances from the solar atmosphere to geospace, including solar flares, CMEs, interplanetary clouds, shock waves, and their geo-effects, such as magnetospheric sub-storms and magnetic storms, and auroral activities. The mission may start at the next solar maximum (launch in about 2012), and with an initial mission lifetime of two to three years. KuaFu data will be used for the scientific study of space weather phenomena, and will be used for space weather monitoring and forecast purposes. The overall mission design, instrument complement, and incorporation of recent technologies will target new fundamental science, advance our understanding of the physical processes underlying space weather, and raise the standard of end-to-end monitoring of the Sun-Earth system.     

火星等离子体环境探测

萤火一号(YH-1)探测器将对火星空间环境进行独立而深入的探测研究,探测各空间区域的等离子体特性及其对太阳风扰动的响应,以及火星离子逃逸过程,研究太阳风对火星水体损失的影响。为了实现这一目标,萤火一号搭载了等离子体探测包,包括2个离子分析器和1个电子分析器,具有较高的时间分辨率、能量分辨率,可以探测0.02～10 keV的离子、电子,同时能够对粒子的入射方向及1～44 au(1 au=9.1095×10~(-31)kg)质量范围内的离子成分进行分辨。本文阐述了萤火一号等离子体探测的科学意义,并对等离子体包的工作原理,仪器设计进行了介绍。     

Cancer risk above 1 Gy and the impact for space radiation protection

Analyses of the epidemiological data on the Japanese A-bomb survivors, who were exposed to γ-rays and neutrons, provide most current information on the dose–response of radiation-induced cancer. Since the dose span of main interest is usually between 0 and 1 Gy, for radiation protection purposes, the analysis of the A-bomb survivors is often focused on this range. However, estimates of cancer risk for doses larger than 1 Gy are becoming more important for long-term manned space missions. Therefore in this work, emphasis is placed on doses larger than 1 Gy with respect to radiation-induced solid cancer and leukemia mortality. The present analysis of the A-bomb survivors data was extended by including two extra high-dose categories and applying organ-averaged dose instead of the colon-weighted dose. In addition, since there are some recent indications for a high neutron dose contribution, the data were fitted separately for three different values for the relative biological effectiveness (RBE) of the neutrons (10, 35 and 100) and a variable RBE as a function of dose. The data were fitted using a linear and a linear-exponential dose–response relationship using a dose and dose-rate effectiveness factor (DDREF) of both one and two. The work presented here implies that the use of organ-averaged dose, a dose-dependent neutron RBE and the bending-over of the dose–response relationship for radiation-induced cancer could result in a reduction of radiation risk by around 50% above 1 Gy. This could impact radiation risk estimates for space crews on long-term mission above 500 days who might be exposed to doses above 1 Gy. The consequence of using a DDREF of one instead of two increases cancer risk by about 40% and would therefore balance the risk decrease described above.     

面向天文观测的空间科学卫星任务规划方法研究

面向天文观测的空间科学卫星任务规划是一个复杂的多目标优化问题.通过对天文观测类卫星的任务规划要素及约束条件进行抽象,建立了面向天文观测的多目标任务规划问题模型,在此基础上设计了基于NSGA-II的多目标观测任务规划算法,并通过实例进行了实验及结果分析.研究表明,该方法能够有效解决天文观测类卫星不同规模的任务规划问题.     

载人火星探测飞行方案

对世界各国载人火星探测的研究情况进行了简要综述,研究了国内外有关载人火星探测飞行方案,提出了载人火星探测方案确定的原则和方案基本思想.给出了一种载人火星探测飞行方案的总体设计,包括飞行轨道方案和载人火星飞船方案等.尤其对轨道设计的重要的两个参数——速度增量和飞行时间进行了详细计算.最后给出了飞行轨道选择、火星飞船从地球到火星和从火星返回地球等的轨道方案和火星飞船各组成部分方案的详细设计结果.     

空间科学任务及其特点综述

人类进入太空以来已经发射了近1万个人造航天器,其中大约10%执行的是空间科学和探测任务.近年来中国经济快速发展,提供了更多的基础研究经费,经济转型也对创新驱动发展提出了更高需求,中国对空间科学的投入开始逐年增加.2015年以来先后成功发射了悟空号、实践十号、墨子号和慧眼号4颗科学卫星,天宫2号空间实验室也成功实施了一系列空间科学实验.重要科学发现和成果正在不断地产出.空间科学卫星任务（或称计划）与应用卫星从提出到评价都有很大不同,因此有必要对其所具有的特点进行分析,从而引导空间科学界从科学团队、技术团队到管理团队提高认识,确保未来的空间科学任务发挥最大效益,获得最大科学产出.     

火星探测无人机任务规划与建模分析

利用无人机进行火星探测, 具有探测范围广、可看到地形变化等优点. 介绍了火星探测无人机总体任务规划的情况, 讨论了探测无人机在火星与地球上飞行的区别, 建立了火星探测无人机纵向非线性模型, 并在平衡点对非线性模型进行泰勒展开, 得到线性化模型. 通过对线性模型的进一步分析, 掌握了火星探测无人机的稳态性能及飞行特点.      

Planetary penetrators: Their origins,history and future

Penetrators, which emplace scientific instrumentation by high-speed impact into a planetary surface, have been advocated as an alternative to soft-landers for some four decades. However, such vehicles have yet to fly successfully. This paper reviews in detail, the origins of penetrators in the military arena, and the various planetary penetrator mission concepts that have been proposed, built and flown. From the very limited data available, penetrator developments alone (without delivery to the planet) have required ∼$30M: extensive analytical instrumentation may easily double this. Because the success of emplacement and operation depends inevitably on uncontrollable aspects of the target environment, unattractive failure probabilities for individual vehicles must be tolerated that are higher than the typical ‘3-sigma’ (99.5%) values typical for spacecraft. The two pathways to programmatic success, neither of which are likely in an austere financial environment, are a lucky flight as a ‘piggyback’ mission or technology demonstration, or with a substantial and unprecedented investment to launch a scientific (e.g. seismic) network mission with a large number of vehicles such that a number of terrain-induced failures can be tolerated.     

Encounter trajectories for deep space mission ASTER to the triple near Earth asteroid 2001-SN263. The laser altimeter (ALR) point of view

In cooperation with Russia, the Brazilian deep space mission ASTER plans to send a small spacecraft to investigate the triple asteroid 2001-SN263. The nearest launch opportunities for this project include June 2022 and June 2025. One main exploration campaign is being planned with focus on the largest asteroid (Alpha). Among the instruments under development, a laser altimeter (named ALR) was preliminarily designed and presented in 2010–2011. Many studies to define mission and instruments requirements were performed aiming at the characterization of important issues for the successful realization of the mission. Among them, the identification of a suitable trajectory that could be followed by the ASTER spacecraft in the encounter phase, when the main campaign will take place. This paper describes the effort undertaken with focus on the laser altimeter operation. Possible encounter trajectories were modelled and simulated to identify suitable approach parameters and conditions allowing the accomplishment of the intended investigation. The simulation also involves the instrument operation, considering approach geometry, attitude, relative motion, time/date, and the dynamics of the main asteroid. From the laser altimeter point of view, keeping in mind the desired coverage results (50% minimum surface coverage of asteroid Alpha, complying with horizontal and vertical resolution requirements), results point out crucial features for the encounter trajectory, like the need for a small inclination (10^-6 degrees; with respect to the asteroid's orbit), the most favourable spacecraft positioning (between the Sun and the asteroid) and pointing condition (back to the Sun), the minimum amount of achievable surface coverage (58%, focused on central areas), and the most proper time to conduct the main campaign (January 2025). Concerning the instrument, results offer refined values for divergence angle (500 to 650 μrad, half-cone), pulse repetition frequencies (from 1/20 to 1 Hz), and consequent data generation rates. A simulation tool that can use any 3D generated trajectories as input data was created for the analyses presented here. Although created for the ALR in this mission, this simple analysis tool can be adapted to other instruments in this or other missions.     

国际空间站智能在轨运行进展及启示

空间站作为近地空间的大型平台,具备长期飞行与空间科学探索能力.随着在轨任务的不断增加,高效空间站在轨运行管理成为挑战性的难题.人工智能与航天技术的深度融合,使得空间站在轨运行逐步向智能化发展,航天器在轨运行智能化已成为必然趋势.本文对国际空间站（International Space Station,ISS）在轨智能化发展历程进行了深入分析,调研人工智能技术在其健康管理、任务规划与调度、任务操作和人机交互中的应用,以期对未来中国空间站的智能在轨运行提供启示.