美国“火星科学实验室”项目成本大增

美国航空航天局（NASA）的“火星科学实验室”（MSL）项目的最初预定成本为15亿美元，就目前来看，其总成本可能超过20亿美元，超支33％-40％。     

空间扫描

美国审计署报告显示美国航空航天局大部分项目延期和预算超支2009年3月，美国审计署发布了《美国航空航天局（NASA）大型项目抽查报告》。报告显示，NASA大部分大型项目延期和预算超支。审计署此次共评估了18个NASA项目，寿命周期成本高达500亿美元，其中13个已经进入执行阶段项目中的10个出现成本超支和进度延迟问题。这10个项目的研发成本与二三年之前评估的成本标准相比平均超出13％，且平均延迟时间达到了11个月。     

美国航宇局的战略规划

□□美国航宇局(NASA)是美国负责发展整个民用航天事业的政府机构,也是一个规模巨大的研制和运营各种民用航天器--载人飞船、深空探测器和卫星,以及研究和开发各种相关技术的实体。NASA下属10个大的研究中心、3个独立的试验和测试机构,其在职人员超过了1.9万人,每年美国政府下拨给它的经费超过100亿美元。1《NASA战略规划2000》20世纪末,NASA在当时的局长丹尼尔·戈尔丁主持下制定了21世纪前25年的战略规划,并作为指令性文件NPD1001.B《NASA战略规划2000》发布。在该战略规划的前言中指出,NASA是对美国未来的投资,目的是大胆地…     

美国自由号空间站的总费用可能达到1180亿美元

美国总会计室(GAO)最近在一份报告中得出结论:航宇局(NASA)严重地低估了“自由”号空间站计划的总费用。NASA和GAO估算金额相差40％。 GAO认为空间站的研制和建造从现在到2000年期间需经费400亿美元,其中包括从1996年底发射入轨后前3年的管理费。按计划空间站的设计寿命为30年,即2027年后空间站寿命结束,加上后27年的管理费,“自由”号空间站计划的总费用将达到1180亿美元。而NASA的估算是:到2000年时共需300亿美元。另外,每年载     

美国NASA 2022财年载人航天运输系统预算分析

1 引言 2021年5月,美国国家航空航天局(NASA)公布了2022财年预算案,预算总额超过248亿美元.其中,载人航天预算项目主要集中于深空探索系统(DSES)以及航天操作两个领域,总预算为108.978 亿美元,约占 NASA 2022 财年总预算的44％.对以上两个领域中与载人航天运输系统相关的项目进行分析,包...     

欧空局研究削减科学卫星计划

欧空局(ESA)拟于90年代实施“海更斯”土卫六探测仪、“星团”磁层观测卫星、“索霍”太阳及太阳层观测卫星三项科学卫星计划。“海更斯”土卫六探测仪是ESA和美航宇局(NASA)合作的项目,它将搭载在NASA的“卡西尼”土星探测器上,然后降落在土星的卫星土卫六上。其总经费为2.5亿美元,今年年底选定主合同单     

美国2022财年航天运输系统发展新动向

正2021年5月底,美国政府对外公布其2022财年预算案,美国国家航空航天局(NASA)、空军(USAF)和天军(USSF)等机构预算中涉及航天运输系统的预算总规模约为73.1 6亿美元,涵盖了研发、采购和运维等多方面的预算项目。通过对各项目内容的分析,以及与往年预算经费的对比,总结了美国在航天运输系统领域的潜在发展方向,可作为未来技术和装备发展的参考信息。1 美国2022财年航天运输项目预算分布情况美国2022财年预算案中,NASA预算经费总计53.21亿美元,空军(含天军)总计19.57亿美元,美国国防高级研究计划局(DARPA)为3700万美元。     

白宫发布2018财年NASA预算

<正>5月23日,白宫发布了2018财年联邦预算案,其中为美国航宇局(NASA)申请的预算为190.92亿美元,比NASA在月初颁布的2017财年综合开支法案下所得经费少了5.61亿美元。根据这项预算,NASA科学、探测、空间运行和其它主要账户都将遭到削减。预算案提出要砍掉NASA的5个被认为不那么重要的地球科学仪器和任务项目,并证实拟关掉NASA教育办公室。NASA表示,这是—份很积极的预算,反映出总统     

美航宇局90年代的空间计划

里根政府1989年的财政预算要求美航宇局提出其未来计划的主要问题(含今后30年空间站的60亿)。按当前美元面值,估计1989年比1988年的90亿要高27％。如果按美航宇局原来的规划(核心计划),到1993年的NASA预算为144亿,到2000年为164亿(1988年面值)。一、核心计划 1972年完成阿波罗登月以后,NASA就制定了研制可重复使用的运输系统、空间平台(很可能是永久载人空间站)和天基数据及通信网络规划。这个长期规划是美国国会预算办公室(CBO)估算NASA预算的起点。对这些主要投资的调整是依据未来的规划(空间科学研究和应用),而不是直接的空间成就。在七八十年代,航天飞机是NASA预     

美国会削减空天飞机和空间站计划经费

美国参众两院委员会除将1990年的空间站计划经费大幅度地削减到18亿美元外,也大大削减了NASA 1990财年X-30空天飞机计划的经费。上星期,拨款委员会打算将NASA要求用于X-30空天飞机的经费削减1.27亿美元。另外,将允许NASA从设施建造项目中转移0.25亿美元经费。拨款委员会批准的NASA总预算为123.8亿美元,包括各种费用在内,总共削减了7.01亿美元。预算批准后,政府将空天飞机计划的2.57亿美元经费分拨给NASA和国防部。     

2005年全球反恐特警队赛记

2005年3月30日到4月2日为期4天，在美国拉斯维加斯举行的全球特警挑战赛（Original World SWAT Challenge,OWSC）中，总计有18支队伍参赛。[编者按]     

Indirect search for Dark Matter with H.E.S.S.

Observations of the Galactic center region with the H.E.S.S. telescopes have established the existence of a steady, extended source of gamma-ray emission coinciding with the position of the super massive black hole Sgr A^*. This is a remarkable finding given the expected presence of dense self-annihilating Dark Matter in the Galactic center region. The self-annihilation process is giving rise to gamma-ray production through hadronization including the production of neutral pions which decay into gamma-rays but also through (loop-suppressed) annihilation into final states of almost mono-energetic photons. We study the observed gamma-ray signal (spectrum and shape) from the Galactic center in the context of Dark Matter annihilation and indicate the prospects for further indirect Dark Matter searches with H.E.S.S.     

The Comet Halley flyby I.R. sounder “I.K.S.”

An infrared sounder is being developed in France to observe in 1986 Comet Halley from the Soviet “VEGA” flyby probes. The instrument, called “I.K.S.”, has three measuring channels. Two of these channels will provide the spectrum of the comet emission in the spectral intervals 2.5–5.0 μ and 6–12 μ, at a constant resolution λ/Δλ = 50.The third channel analyzes the comet I.R. image at a spatial frequency of about 1 arc minute^?1; two I.R. colours are used in this channel: 7–10 μ and 10–14 μ. From the results expected, it is hoped that (1) most primary simple molecules emitted by the nucleus will be identified; (2) the chemical composition and perhaps crystalline structure of the dust grains and ices released by the comet will be derived; and (3) the diameter of the nucleus and its brightness temperatures will be measured.     

The C.E.B.A.S.-Minimodule: behaviour of an artificial aquatic ecological system during spaceflight.

The C.E.B.A.S.-Minimodule, a closed aquatic ecosystem integrated into a middeck locker and consisting of a Zoological (animal tanks), a Botanical (plant bioreactor), a Microbial (bacteria filter) and an Electronic Component (data acquisition/control system) was flown on the STS-89 spaceshuttle mission in January 1998 for 9 days. Preflight the plant bioreactor was loaded with 53 g of Ceratophyllum demersum (coontail) and the animal tanks with 4 adult pregnant females of the fish, Xiphophorus helleri (sword-tails), 200 juveniles of the same species less than 1 week of age, 38 large and 30 juvenile Biomphalaria glabrata water snails. The filter compartment was filled with 200 g of lava grain inoculated with laboratory strains of ammonia-oxidizing bacteria. A ground reference was undertaken with the same biological setup with a delay of 4 d. After an adaptation period of 5 d the system was closed and integrated into the spaceshuttle one day before launch. Video recordings of the animals were automatically taken for 10 minutes in 2-hour periods; the tapes were changed daily by the astronauts. The chemical and physical data for the aquatic system were within the expected range and were closely comparable in comparison to the ground reference. After 9 d under space conditions, the plant biomass increased to 117 g. The plants were all found in very good condition. All 4 adult female fish were retrieved in a good physiological condition. The juvenile fishes had a survival rate of about 33%. Almost 97% of the snails had survived and produced more than 250 neonates and 40 spawning packs. All samples were distributed according to a defined schedule and satisfied all scientific needs of the involved 12 principal investigators. This was the first successful spaceflight of an artificial aquatic ecosystem containing vertebrates, invertebrates, higher plants and microorganisms self-sustained by its inhabitants only. C.E.B.A.S. in a modified form and biological setup is a promising candidate for the early space station utilization as a first midterm experiment.     

Mechanisms underlying cellular radiosensitivity and R.B.E.: introductory remarks.

A general outline of the symposium titled "Mechanisms underlying cellular radiosensitivity and R.B.E." will be given in the introduction. The essential topics of molecular radiation biology are described with respect to the damage, repair and mutagenesis caused by high-LET irradiation to cellular DNA. The importance of clustered DNA lesions (locally multiply damaged sites) formed in vivo is discussed. This symposium is devoted to the mechanisms of the biological effects of radiation with high LET, especially with regard to the effects of heavy ions and neutrons which may cause possible risks in space flight, (e.g. carcinogenesis and mutagenesis). Detailed understanding of these risks, however, demands knowledge of the molecular mechanisms involved in the biological effects of high-LET radiations. Thus, it was the organizers' idea to hold a symposium dealing with primary physical and chemical events caused in cellular deoxyribonucleoproteins by densely-ionizing radiations and to relate them to track structures and energy transfer processes. The mechanisms of DNA damage were regarded from different points of view including those considering DNA repair and mutagenesis. Problems associated with cell survival and radiation protection were discussed as well. Our knowledge of the molecular mechanisms of high-LET radiation actions, however, is limited compared to what we know about low-LET radiation effects (e.g. from gamma-rays or X-rays). To emphasize this statement, I would like to summarize briefly the open questions in molecular radiation biology, what we know already about low-LET effects and what is lacking describing the effect of high-LET radiation.     

The "C.E.B.A.S. MINI-MODULE": a self-sustaining closed aquatic ecosystem for spaceflight experimentation.

The C.E.B.A.S. MINI-MODULE is the miniaturized space flight version of the Closed Equilibrated Biological Aquatic System (C.E.B.A.S.). It fits into a large middeck locker tray and is scheduled to be flown in the STS 85 and in the NEUROLAB missions. Its volume is about 9 liters and it consists of two animal tanks, a plant cultivator, and a bacteria filter in a monolithic design. An external sensor unit is connected to a data acquisition/control unit. The system integrates its own biological life support. The CO2 exhaled by the consumers (fishes, snails, microorganisms) is assimilated by water plants (Ceratophyllum demersum) which provide them with oxygen. The products of biomass degradation and excretion (mainly ammonia ions) are converted by bacteria into nitrite and nitrate. The latter is taken up by the plants as a nitrogen source together with other ions like phosphate. The plants convert light energy into chemical energy and their illumination is regulated via the oxygen concentration in the water by the control unit. In ground laboratory tests the system exhibited biological stability up to three month. The buffer capacity of the biological filter system is high enough to eliminate the degradation products of about one half of the dead animal biomass as shown in a "crash test". A test series using the laboratory model of the flight hardware demonstrated the biological stability and technical reliability with mission-identical loading and test duration. A comprehensive biological research program is established for the C.E.B.A.S. MINI-MODULE in which five German and three U.S.-American universities as well as the Russian Academy of Sciences are involved.     

C.E.B.A.S. MINI MODULE: test results of an artificial (man-made) aquatic ecosystem.

The original Closed Equilibrated Biological Aquatic System (C.E.B.A.S.) is a long-term multi-generation research facility for experiments with aquatic animals and plants in a space station the development of which is surrounded by a large international scientific program. In addition, a miniaturized laboratory prototype, the C.E.B.A.S. MINI MODULE, with a total volume of about 10-12 liters for a Spacelab middeck locker was developed and a first version was tested successfully for two weeks with a population of fishes (Xiphophorus helleri) in the animal tank and a Ceratophyllum spec. in the illuminated higher plant growth chamber. The water recycling system consisted of a bacteria filter and a mechanical filter and the silastic tubing gas exchanger was separated by valves for the utilization in emergency cases only. Data were collected with the acquisition module of the original C.E.B.A.S. process control system. In addition, an optimized version was tested for 7 weeks with fishes and plants and thereafter with fish and with plants only for 2 and 1 weeks, resp.. The paper presents the relevant water parameters (e.g., pH, pressure, temperature, oxygen saturation, flow rate, ion concentrations) during the test period as well as morphological and physiological data of the enclosed animals and plants. On the basis of the given results the possible role of the C.E.B.A.S. system as a scientific tool in artificial ecosystem research and for the development of a combined animal-plant intensive aquaculture system and its utilization in bioregenerative life support is discussed.     

Aquatic modules for bioregenerative life support systems: developmental aspects based on the space flight results of the C.E.B.A.S. MIN-MODULE.

The Closed Equilibrated Biological Aquatic System (C.E.B.A.S.) is an artificial aquatic ecosystem which contains teleost fishes, water snails, ammonia oxidizing bacteria and edible non-gravitropic water plants. It serves as a model for aquatic food production modules which are not seriously affected by microgravity and other space conditions. Its space flight version, the so-called C.E.B.A.S. MINI-MODULE was already successfully tested in the STS-89 and STS-90 (NEUROLAB) missions. It will be flown a third time in space with the STS-107 mission in January 2003. All results obtained so far in space indicate that the basic concept of the system is more than suitable to drive forward its development. The C.E.B.A.S. MINI-MODULE is located within a middeck locker with limited space for additional components. These technical limitations allow only some modifications which lead to a maximum experiment time span of 120 days which is not long enough for scientifically essential multi-generation-experiments. The first necessary step is the development of "harvesting devices" for the different organisms. In the limited space of the plant bioreactor a high biomass production leads to self-shadowing effects which results in an uncontrolled degradation and increased oxygen consumption by microorganisms which will endanger the fishes and snails. It was shown already that the latter reproduce excellently in space and that the reproductive functions of the fish species are not affected. Although the parent-offspring-cannibalism of the ovoviviparous fish species (Xiphophorus helleri) serves as a regulating factor in population dynamics an uncontrolled snail reproduction will also induce an increased oxygen consumption per se and a high ammonia concentration in the water. If harvesting locks can be handled by astronauts in, e. g., 4-week intervals their construction is not very difficult and basic technical solutions are already developed. The second problem is the feeding of the animals. Although C.E.B.A.S.-based aquaculture modules are designed to be closed food loop systems (edible herbivorous fish species and edible water plants) which are already verified on Earth this will not be possible in space without devices in which the animals are fed from a food storage. This has to be done at least once daily which would waste too much crew time when done by astronauts. So, the development of a reliable automated food dispenser has highest priority. Also in this case basic technical solutions are already elaborated. The paper gives a comprehensive overview of the proposed further C.E.B.A.S.-based development of longer-term duration aquatic food production modules.     

V.L.A. observations of flare build-up in coronal loops

Very Large Array (V.L.A.) measurements at 20 cm wavelength map emission from coronal loops with second-of-arc angular resolution at time intervals as short as 3.3 seconds. The total intensity of the 20 cm emission describes the evolution and structure of the hot plasma that is detected by satellite X-ray observations of coronal loops. The circular polarization of the 20 cm emission describes the evolution, strength and structure of the coronal magnetic field. Preburst heating and magnetic changes that precede burst emission on time scales of between 1 and 30 minutes are discussed. Simultaneous 20 cm and soft X-ray observations indicate an electron temperature $\text{T}{}_{\mathrm{e}}\textcolor{red}{}\text{2.5 × 10}{}^7\text{K}$ and electron density $\text{N}{}_{\mathrm{e}}\textcolor{red}{}\text{10}{}^{10}\text{cm}{}^{\mathrm{?3}}$ during preburst heating in a coronal loop that was also associated with twisting of the entire loop in space. We also discuss the successive triggering of bursts from adjacent coronal loops; highly polarized emission from the legs of loops with large intensity changes over a 32 MHz change in observing frequency; and apparent motions of hot plasma within coronal loops at velocities V > 2,000 kilometerspersecond.     

美国的战斧巡航导弹

3月19日,美英法三国开始对利比亚实行军事打击。在当天进行的空袭行动中,部署在地中海的美军和英军军舰与潜艇就向利比亚首都的黎波里郊区和东部城市米苏拉塔等地发射了110多枚战斧巡航导弹,袭击了20多处防空设施和民事目标。在随后的几天里,每天又都发射了一批这种导弹。截止到4月1日,美军共发射了221枚、英军共发射了7枚战斧巡航导弹。那么,战斧巡航导弹究竞