“猎鹰”9号的复用技术与展望

正"猎鹰"9号火箭在第20次发射中,第一级火箭返回并着陆成功,成为人类火箭工业发展的重要里程碑。"猎鹰"9号火箭的研制者太空探索技术公司执着地追求运载火箭的复用,在复用技术上进行了大量探索,这次成功开创了运载火箭重复使用的新途径。这条道路无论在技术上还是在商业上都是可圈可点的。坚持不懈的努力"猎鹰"9号火箭是目前太空探索     

乘坐“气球”去飞天?

正2016年4月8日,美国太空探索技术公司的"猎鹰"9号火箭成功地执行了一次发射任务。本次发射后,"猎鹰"9号第一级成功返回海上回收平台,举世惊艳。而本次任务另外一个亮点却被人们暂时性地忽视了,那就是比格罗航天公司的充气式太空舱"比格罗可扩展行为舱"(BEAM)。而且,比格罗这位连锁酒店的老板不仅仅打算把太空舱送到国际空间站上,还打算发射并运行完整的空间站,甚至把充     

艾伦·马斯克的终极梦想——可重复使用运载火箭

<正>2014年4月18日,Space X公司的"猎鹰"9号V1.1型火箭执行国际空间站货运发射任务时,第一级箭体成功实现了受控再入和软落水,"蚱蜢"试验飞行器也连续成功,这似乎预示着Space X可重复使用运载火箭的研制已经看到了胜利的曙光。作为一家新兴航天企业,Space X在不过十二年的历史上,取得了举世瞩目的成绩。他们的"龙"货运飞船和"猎鹰"9号运载火箭的研制都     

美国

<正>"猎鹰"9发射"回声星"233月16日,太空探索公司的"猎鹰"9-1.2型运载火箭在卡纳维拉尔角肯尼迪航天中心发射了回声星公司的"回声星"23通信卫星。由于要发射的卫星质量较大等原因,本次发射采用的是"猎鹰"9-1.2型火箭的一次性使用型号,去掉了第一级下部通常配备的4条着陆支腿,未进行第一级着陆回收。这是"猎鹰"9火箭2015年4月以来首次采用一次性使用配置发射,也是"猎鹰"9火箭第二次在肯尼迪航天中心的第39A号发射台发射。"回声星"23由劳拉空间系统公司生产,采用劳拉1300系列平台建造,发射质量约5500千克,配备Ku、Ka和S波段转发器,它将被部署在巴西上空的西经44.9度轨位,用于直播到户电视广播等业务,设计寿命15年以上。(江山)     

“猎鹰9号”发射高通量通信卫星

正2019年12月16日,太空探索技术公司的猎鹰9-1.2型运载火箭在卡纳维拉尔角空军基地第40号工位发射了由新加坡创企Kacific宽带卫星集团和日本天空完美日星公司共同拥有的Kacific-1/"日本通信卫星"(JCSAT)18高通量卫星。这是"猎鹰9号"火箭11天内第二次从该发射台发射,创下了该公司同一发射台两次发射之间用时最短的纪录。     

太空新航线

轨道通信公司第二代卫星转由"猎鹰"9发射美国卫星信息传输服务商轨道通信公司的18颗第二代卫星要到今年春天才能开始交付发射,而前两颗卫星将改由太空探索技术公司的大型"猎鹰"9火箭搭     

“猎鹰”9船上着陆再败

正3月4日,太空探索技术公司的"猎鹰"9FT型运载火箭在卡纳维拉尔角空军站发射了卢森堡欧洲卫星公司(SES)的SES-9通信卫星。这次发射再次进行了火箭第一级海上平台着陆尝试,但依然未能取得成功。这是"猎鹰"9火箭2015年6月底发射失败后的第三次发射,也是"猎鹰"9FT型火箭第二次发射和首次执行静地转移轨道发射任务。本次发射也是太空探索公司今年的第二次发射。     

从屡战屡败到习以为常——“猎鹰”火箭回收技术逐步成熟

<正>1月15日凌晨1点54分,10颗新一代铱星由太空探索技术公司的"猎鹰"9号火箭成功发射,这是去年9月1日"阿莫斯"6卫星事故后"猎鹰"火箭重整旗鼓的一次发射,火箭第一级也成功实现了海上回收。时至今日,"猎鹰"火箭的一级回收试验从屡战屡败发展到众人习以为常,一级火箭的反推垂直降落回收技术逐步成熟。     

“复用”之路越走越宽——航天史上首艘“二手”货运飞船升空

<正>北京时间6月4日清晨5点07分,美国太空探索技术公司(SpaceX)利用旗下猎鹰9号火箭成功将同为该公司研发的"龙"飞船发射升空。该艘"龙"飞船执行的是第11次国际空间站货运补给任务。此次发射并不是一次平凡的发射,因为这次发射的"龙"飞船是人类航天史上第一艘重复使用的飞船。一次不平凡的发射在猎鹰9号火箭回收再利用之后,SpaceX并没有满足于"二手"火箭     

NROL-76发射:猎鹰火箭的新里程碑

<正>2017年5月1日晚上19时15分,"猎鹰"9号火箭从肯尼迪航天中心将美国国家侦察局的NROL-76卫星发射升空,这是太空探索技术公司首次发射高度机密的军用载荷,是该公司进入军用发射市场的里程碑。这次发射中"猎鹰"9号火箭第一级实现了教科书式返回和回收,二级长时间滑行后再次点火,也为执行难度更高的静止轨道直送任务奠定了基础。     

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