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1.
The Discovery Program is a rarity in the history of NASA solar system exploration: a reform program that has survived and continued to be influential. This article examines its emergence between 1989 and 1993, largely as the result of the intervention of two people: Stamatios “Tom” Krimigis of the Johns Hopkins University Applied Physics Laboratory (APL), and Wesley Huntress of NASA, who was Division Director of Solar System Exploration 1990–92 and the Associate Administrator for Space Science 1992–98. Krimigis drew on his leadership experience in the space physics community and his knowledge of its Explorer program to propose that it was possible to create new missions to the inner solar system for a fraction of the existing costs. He continued to push that idea for the next two years, but it took the influence of Huntress at NASA Headquarters to push it on to the agenda. Huntress explicitly decided to use APL to force change on the Jet Propulsion Laboratory and the planetary science community. He succeeded in moving the JPL Mars Pathfinder and APL Near Earth Asteroid Rendezvous (NEAR) mission proposals forward as the opening missions for Discovery. But it took Krimigis's political skill and access to Sen. Barbara Mikulski in 1993 to get the NEAR into the NASA budget, thereby likely ensuring that Discovery would not become another one-mission program.  相似文献   

2.
China has seen a dramatic acceleration in the scope and capabilities of its space program in the past decade. This has been coupled with significantly increased global economic presence and influence as well as a steady improvement of its military capabilities. China's emergence as a major world actor has encouraged the emergence of a ‘China threat’ school of thought which interprets all Chinese policy, including its space program, as an evidence of a threatening challenge to US dominance in which the pursuit of a range of military space capabilities plays a central role. This article challenges that interpretation, arguing that China's space program is the product of a range of factors including powerful domestic political and developmental rationales and that the program is overwhelmingly driven by domestic rather than international considerations, particularly in terms of the use of the program for the purposes of enhancing prestige.  相似文献   

3.
The Space Station Freedom will be a permanently manned, low-Earth orbit research facility, elements of which are being provided by the United States, Canada, countries of the European Space Agency and Japan. The facility will be assembled in space and operated well into the twenty-first century. The ground infrastructure must be able to support both assembly and long-term operations. The infrastructure will consist of ground facilities, support systems and the associated planning and management procedures. The key facilities identified to support Space Station Freedom Program (SSFP) integrated operations and their SSFP roles will be described in detail in this paper.

Requirements for the integrated ground infrastructure are developed and controlled within the SSFP requirements documentation and baselining processes. A Ground Systems Program directive summarizes key operations functions, roles and responsibilities of the various program participants. During 1992, the SSFP is conducting a major program review of the ground infrastructure including the definition of all facility and support system functional capabilities, interfaces and dataflow requirements. Operations functionality and interface verification tests are being identified and operations readiness dates are being established.  相似文献   


4.
As economic pressure and competition for budget among federal agencies has increased, there has been an increasing need for more granular data and robust management information systems. This is especially true for the execution of major civilian space programs. This need has resulted in new program management requirements being implemented in an attempt to limit cost and schedule growth. In particular, NASA Procedural Requirements (NPR) 7120.5D requires the implementation of an Earned Value Management System (EVMS) compliant with the requirements of American National Standards Institute (ANSI)/Electronic Industries Alliance Standard 748-B. The Radiation Belt Storm Probes (RBSP) program management team at The Johns Hopkins University Applied Physics Laboratory (JHU/APL) made a decision to implement an EVMS on RBSP during Phase B—a year earlier than specified in the contractual Phase C reporting requirement as defined in the NPR. This decision was made so that the project would have the benefit of 12 months of training and hands-on implementation during Phase B. Although there were a number of technical and process hurdles encountered during Phase B and into Phase C, the system was working well when the Integrated Baseline Review (IBR) was held in August 2009. The IBR was a success because it met the review requirements. It was also clear to all IBR participants that the EVMS was providing value to the project management team. Although the IBR pointed out some areas of concern regarding process and ANSI compliance, the system had markedly improved the project's ability to monitor cost and schedule. This, in turn, allowed the project team to foresee problems in advance, formulate corrective actions, and implement course corrections without causing significant adverse impact to the project. Opponents of EVMS systems often communicate the unfavorable opinion that EVMS systems create unnecessary cost and administration. Although it is undeniable that EVMS implementation does not occur without cost, the cost is minimal in comparison to the benefits of successful implementation. This paper will focus on the implementation of EVMS on the RBSP project, explain EV processes and the implementation's cost, and analyze the benefits of EVMS to provide insight into cost/benefit considerations for other projects considering EVMS implementation. This paper will do this by focusing on the following points: (1) RBSP is the first full-up implementation of earned value management (EVM) at JHU/APL; (2) RBSP EVM started in Phase B; (3) RBSP EVM implementation has been working well in Phase C/D; (4) RBSP EVM implementation has been recognized by Goddard Space Flight Center and NASA Headquarters as successful; and (5) an assessment of the benefits of EVMS to the project management team and sponsor shows that the system's benefits outweigh the cost of implementation.  相似文献   

5.
Joseph N. Pelton   《Space Policy》2010,26(4):246-248
The Space Transportation System (STS), for better or worse, has dominated the US space program for some 30 years and is now an American icon. The Space Shuttle orbiters have flown over 120 missions and certainly accomplished some amazing feats, including the deployment of the International Space Station (ISS), the launch and double repair of the Hubble Telescope, a number of classified missions for the US defense establishment and the cementing of international cooperation in space. As the remaining Space Shuttle orbiters head toward various museums, it is timely to look at the STS program in terms of key US space policy decisions that have paralleled the Space Shuttle’s often troubled history. This article seeks, from both a historical and a policy perspective, to assess what might have been. While noting the major accomplishments of the STS, it also identifies what can best be characterized as major lost opportunities and flawed policy decisions that have had multi-billion dollar consequences. In this regard, the US Congress, the White House, and NASA leadership have all played a role. If there have been failings, they have not been by NASA alone, but the entire US space policy leadership.  相似文献   

6.
In the absence of a mature body of literature on the origins and evolution of the Canadian space program, recent official publications have arbitrarily chosen 1974, the year that Canada's civilian space policy was ratified in the House of Commons, as the popular date of origin. However, this start date ignores several significant policy documents that influenced Canada's space program development prior to that year. This article examines policy that shaped Canada's space program during the ‘golden age’ of space exploration (1958–1974), and will demonstrate that the true origins of the Canadian space program date back much earlier that the current perception.  相似文献   

7.
美国高超声速技术飞行器   总被引:3,自引:0,他引:3  
介绍了美国正在开展的猎鹰计划及该计划的目标、组成和各组成部分的任务目标。重点介绍了该计划下研制的高超声速技术飞行器(HTV)。此外,还对HTV所涉及的关键技术进行了总结。  相似文献   

8.
The current emphasis on smaller, faster, cheaper (SFC) spacecraft in NASA’s solar system exploration program is the product of a number of interacting – even interdependent – factors. The SFC concept as applied to NASA’s solar system exploration program can be viewed as the vector sum of (1) the space science community’s desire for more frequent planetary missions to plug the data gaps, educate the next generation of scientists, provide missions to targets of opportunity, and enable programmatic flexibility in times of budgetary crisis; (2) the poor publicity garnered by NASA in the early 1990s and the resultant atmosphere of public criticism (creating an opportunity for reform); (3) The Strategic Defense Initiative Organization’s and the National Space Council community’s desire to advance the Space Exploration Initiative and their perception that the NASA culture at the time represented a barrier to the effective pursuit of space exploration; (4) the effective leadership of NASA Administrator Daniel Goldin; and (5) the diminishing budget profile for space sciences in the early 1990s. This paper provides a summary of the origin of the smaller, faster, cheaper approach in the planetary program. A more through understanding of the history behind this policy will enable analysts to assess more accurately the relative successes and failures of NASA’s new approach to solar system exploration.  相似文献   

9.
《Acta Astronautica》2011,68(11-12):1443-1450
For over 100 years, transient luminous phenomena have been seen in the Hessdalen valley. Italian and Norwegian scientists, gaining experience from the SETI program, has since 1998 installed cameras, spectrometers and RADAR's to unveil the nature of this phenomenon. Results indicate a combustion process driven by an unknown power source.  相似文献   

10.
俄罗斯空间站推进剂补加程序分析   总被引:5,自引:0,他引:5  
江铭伟 《火箭推进》2013,39(4):8-12
补加程序是推进剂补加系统的关键技术之一,而目前也仅有俄罗斯有成功应用的经验.根据目前获取的资料,经过计算、仿真和论证,对俄罗斯空间站的补加系统进行了研究,分析了ATV对空间站进行推进剂补加的程序,初步得到了俄罗斯空间站推进剂补加的特点,可作为目前我国空间站方案论证期间补加程序的参考.  相似文献   

11.
The UK civil space strategy for the years 2008–2012 and beyond was published in February 2008. This paper describes the key features of the strategy and highlights those areas that are new or different from the aims set out in previous strategies. In particular, the strategy lays out a new five-part high-level vision for UK civil space.  相似文献   

12.
The Small Satellite Technology Initiative (SSTI) is a National Aeronautics and Space Administration (NASA) program to demonstrate smaller, high technology satellites constructed rapidly and less expensively. Under SSTI, NASA funded the development of “Clark,” a high technology demonstration satellite to provide 3-m resolution panchromatic and 15-m resolution multispectral images, as well as collect atmospheric constituent and cosmic x-ray data. The 690-Ib. satellite, to be launched in early 1997, will be in a 476 km, circular, sun-synchronous polar orbit. This paper describes the program objectives, the technical characteristics of the sensors and satellite, image processing, archiving and distribution. Data archiving and distribution will be performed by NASA Stennis Space Center and by the EROS Data Center, Sioux Falls, South Dakota, USA.  相似文献   

13.
Despite its scientific successes, NASA has over the past two decades lost its way, spending billions of dollars on transportation systems that have at bottom been failures. President Obama's cancellation of the costly and unwieldy Constellation program provides an opportunity for genuine reform of the agency and the US space program, through harnessing the innovatory and cost-effective power of commercial entrepreneurs. Examples of the kinds of project they might undertake – including solar power satellites, ‘space taxis’ and a space elevator – are discussed.  相似文献   

14.
鉴于火工装置研制现在缺少一套完整的可靠性设计、试验、评估方法与程序,文章从实际使用角度出发,总结了一套方法和程序,主要介绍火工装置可靠性模型,各个环节的可靠性设计、试验方法,并叙述了现型号使用的可靠性评估方法和程序。  相似文献   

15.
The NASA Radiation Belt Storm Probes (RBSP) mission, currently in Phase B, is a two-spacecraft, Earth-orbiting mission, which will launch in 2012. The spacecraft's S-band radio frequency (RF) telecommunications subsystem has three primary functions: provide spacecraft command capability, provide spacecraft telemetry and science data return, and provide accurate Doppler data for navigation. The primary communications link to the ground is via the Johns Hopkins University Applied Physics Laboratory's (JHU/APL) 18 m dish, with secondary links to the NASA 13 m Ground Network and the Tracking and Data Relay Spacecraft System (TDRSS) in single-access mode. The on-board RF subsystem features the APL-built coherent transceiver and in-house builds of a solid-state power amplifier and conical bifilar helix broad-beam antennas. The coherent transceiver provides coherency digitally, and controls the downlink data rate and encoding within its field-programmable gate array (FPGA). The transceiver also provides a critical command decoder (CCD) function, which is used to protect against box-level upsets in the C&DH subsystem. Because RBSP is a spin-stabilized mission, the antennas must be symmetric about the spin axis. Two broad-beam antennas point along both ends of the spin axis, providing communication coverage from boresight to 70°. An RF splitter excites both antennas; therefore, the mission is designed such that no communications are required close to 90° from the spin axis due to the interferometer effect from the two antennas. To maximize the total downlink volume from the spacecraft, the CCSDS File Delivery Protocol (CFDP) has been baselined for the RBSP mission. During real-time ground contacts with the APL ground station, downlinked files are checked for errors. Handshaking between flight and ground CFDP software results in requests to retransmit only the file fragments lost due to dropouts. This allows minimization of RF link margins, thereby maximizing data rate and thus data volume.  相似文献   

16.
The results of investigating free oscillations of the International Space Station construction appearing during spacecraft docking and undocking are described. The study is carried out using the measurement data of the low-frequency MAMS accelerometer. Several intervals of measurements performed in 2005 and 2006 were chosen to be studied. For chosen intervals, only the data intervals corresponding to the process of free attenuation of the oscillations construction elements were analyzed. Characteristic frequencies of elastic oscillations of the station construction and attenuation coefficients corresponding to them are found. The comparative analysis of the results obtained for various docking ports (nodes) is carried out. The described study is performed as a part of the technical experiment “The ISS Environment” carried out onboard the station in accordance with the Russian program of scientific and engineering experiments.  相似文献   

17.
美国空军正在研发一种具备“分身术”的新型卫星系统——F6系统。由这种未来的绕地“虚拟卫星”组成的系统将具有强大的侦察功能,会把敌方军队窥探无余,一旦其中的某颗卫星被击落,将会有新的卫星很快替补上去。描述了美国国防高级研究计划局(DARPA)提出的这个计划的概况和进展情况,并提出该计划实施的关键技术。  相似文献   

18.
飞行训练弹设计方案探讨   总被引:1,自引:0,他引:1  
论述了研制半主动雷达寻的空空导弹训练弹的必要性,提出了训练弹设计方案的基本要求及关键所在,在分析导弹工作过程的基础上,指出必须提供具有逻辑功能的模拟信号和故障设置。通过举例对准备程序和点火程序逻辑功能电路的探讨提出了训练弹电路设计方案的基本构想。  相似文献   

19.
《Acta Astronautica》2001,48(5-12):817-825
This paper will provide an overview of the Iridium business venture in terms of the challenges faced, the successes achieved, and the causes of the ultimate failure of the venture — bankruptcy and system de-orbit. The paper will address technical, business, and policy issues. The intent of the paper is to provide a balanced and accurate overview of the Iridium experience, to aid future decision-making by policy makers, the business community, and technical experts. Key topics will include the history of the program, the objectives and decision-making of Motorola, the market research and analysis conducted, partnering strategies and their impact, consumer equipment availability, and technical issues — target performance, performance achieved, technical accomplishments, and expected and unexpected technical challenges. The paper will use as sources trade media and business articles on the Iridium program, technical papers and conference presentations, Wall Street analyst's reports, and, where possible, interviews with participants and close observers.  相似文献   

20.
The widely distributed nature of the Space Station Freedom program, plus continuous multi-year operations will force program planners to develop innovative planning concepts. The traditional centralized planning operation will not be adequate. It will be replaced by multiple small planning centers working within guidelines issued by a central planning authority. Plans will not be optimized; rather, operating efficiency and user flexibility will be blended to satisfy program goals. The key to this new approach is the application of new planning methodologies and system development technologies to accommodate distributed resources that must be integrated. Resources will be distributed to the multiple planning entities in such a way that, when the several plans are built and then integrated, they will fit together with minimal modification. The plan itself will be an envelope schedule containing resource limits and constraint boundaries within which users will be free to make choices of the specific activities they will execute, up to the time of execution. Some level of margin within program guidelines will be built in to allow for variation and unforeseen change. This paper presents the authors' recommended planning approach and cites two NASA systems being developed that will utilize these resource distribution/integration planning concepts, methodologies and development technologies.  相似文献   

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