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1.
Using economic incentives to control costs is a new concept for space missions. The basic tenets of market-based approaches run counter to typical centralized management techniques often utilized for complex space missions. NASA's Cassini mission to Saturn used a market trading system to assist the Science Instrument Manager in guiding the development of the spacecraft's science payload. This system allowed science instrument teams to trade resources among themselves to best manage their resources (mass, power, data rate, and budget). Thus, Cassini Project management was no longer responsible for adjudicating and reallocating resources that result from instrument development problems. Instrument teams were responsible for directly managing their resources and if they ran into a development problem it was their responsibility to resolve their problem by descoping or through the use of a 'resource exchange.' Under the trading system, instrument cost growth was less than 1% and the total payload mass was under its allocation by 7%. This result is in stark contrast to the 50%–100% increases in these resources on past missions.  相似文献   

2.
This paper proposes an approach for a complex and innovative project requiring international contributions from different communities of knowledge and expertise. Designing a safe and reliable architecture for a manned mission to Mars or the Asteroids necessitates strong cooperation during the early stages of design to prevent and reduce risks for the astronauts at each step of the mission. The stake during design is to deal with the contradictions, antagonisms and paradoxes of the involved partners for the definition and modeling of a shared project of reference. As we see in our research which analyses the cognitive and social aspects of technological risks in major accidents, in such a project, the complexity of the global organization (during design and use) and the integration of a wide and varie d range of sciences and innovative technologies is likely to increase systemic risks as follows: human and cultural mistakes, potential defaults, failures and accidents. We identify as the main danger antiquated centralized models of organization and the operational limits of interdisciplinarity in the sciences. Beyond this, we can see that we need to take carefully into account human cooperation and the quality of relations between heterogeneous partners. Designing an open, self-learning and reliable exploration system able to self-adapt in dangerous and unforeseen situations implies a collective networked intelligence led by a safe process that organizes interaction between the actors and the aims of the project. Our work, supported by the CNES (French Space Agency), proposes an innovative approach to the coordination of a complex project.  相似文献   

3.
Spore-forming bacteria are of particular concern in the context of planetary protection because their tough endospores may withstand certain sterilization procedures as well as the harsh environments of outer space or planetary surfaces. To test their hardiness on a hypothetical mission to Mars, spores of Bacillus subtilis 168 and Bacillus pumilus SAFR-032 were exposed for 1.5 years to selected parameters of space in the experiment PROTECT during the EXPOSE-E mission on board the International Space Station. Mounted as dry layers on spacecraft-qualified aluminum coupons, the "trip to Mars" spores experienced space vacuum, cosmic and extraterrestrial solar radiation, and temperature fluctuations, whereas the "stay on Mars" spores were subjected to a simulated martian environment that included atmospheric pressure and composition, and UV and cosmic radiation. The survival of spores from both assays was determined after retrieval. It was clearly shown that solar extraterrestrial UV radiation (λ≥110?nm) as well as the martian UV spectrum (λ≥200?nm) was the most deleterious factor applied; in some samples only a few survivors were recovered from spores exposed in monolayers. Spores in multilayers survived better by several orders of magnitude. All other environmental parameters encountered by the "trip to Mars" or "stay on Mars" spores did little harm to the spores, which showed about 50% survival or more. The data demonstrate the high chance of survival of spores on a Mars mission, if protected against solar irradiation. These results will have implications for planetary protection considerations.  相似文献   

4.
We have developed the space suit simulator Aouda.X, which is capable of reproducing the physical and sensory limitations a flight-worthy suit would have on Mars. Based upon a Hard-Upper-Torso design, it has an advanced human-machine interface and a sensory network connected to an On-Board Data Handling system to increase the situational awareness in the field. Although the suit simulator is not pressurized, the physical forces that lead to a reduced working envelope and physical performance are reproduced with a calibrated exoskeleton. This allows us to simulate various pressure regimes from 0.3-1 bar. Aouda.X has been tested in several laboratory and field settings, including sterile sampling at 2800 m altitude inside a glacial ice cave and a cryochamber at -110°C, and subsurface tests in connection with geophysical instrumentation relevant to astrobiology, including ground-penetrating radar, geoacoustics, and drilling. The communication subsystem allows for a direct interaction with remote science teams via telemetry from a mission control center. Aouda.X as such is a versatile experimental platform for studying Mars exploration activities in a high-fidelity Mars analog environment with a focus on astrobiology and operations research that has been optimized to reduce the amount of biological cross contamination. We report on the performance envelope of the Aouda.X system and its operational limitations.  相似文献   

5.
Japan's Consultative Committee on Long Term Policy was established within the Space Activities Commission to consider how the country's space activities should proceed. The Committee was asked to take a long-term viewpoint, considering the rapid changes in both domestic and overseas space activities. This report is an edited version (and unofficial translation) of the Committee's report, published in May 1987. It outlines the significance of space activities for Japan, considers how they have developed during this century, forecasts development after the year 2000, and presents proposals for the execution of Japan's space development.  相似文献   

6.
The NASA Deep Space Network (DSN) has a new requirement to support high-data-rate Category A (Cat A) missions (within 2 million kilometers of the Earth) with simultaneous S-band uplink, S-band downlink and Ka-band downlink. The S-band links are required for traditional telemetry, tracking & command (TT&C) support to the spacecraft, while the Ka-band link is intended for high-data-rate science returns. The new Ka-band system combines the use of proven DSN cryogenic designs, for low system temperature, and high-data-rate capability using commercial telemetry receivers. The initial Cat A support is required for the James Webb Space Telescope (JWST) in 2014 and possibly other missions. The upgrade has been implemented into 3 different 34-meter Beam Waveguide (BWG) antennas in the DSN, one at each of the complexes in Canberra (Australia), Goldstone (California) and Madrid (Spain). System test data are presented to show that the requirements were met and the DSN is ready for Cat A Ka-band operational support.  相似文献   

7.
8.
Chandrayaan-1 is the first Indian planetary exploration mission that will perform remote sensing observation of the Moon to further our understanding about its origin and evolution. Hyper-spectral studies in the 0.4– region using three different imaging spectrometers, coupled with a low energy X-ray spectrometer, a sub-keV atom analyzer, a 3D terrain mapping camera and a laser ranging instrument will provide data on mineralogical and chemical composition and topography of the lunar surface at high spatial resolution. A low energy gamma ray spectrometer and a miniature imaging radar will investigate volatile transport on lunar surface and possible presence of water ice in the polar region. A radiation dose monitor will provide an estimation of energetic particle flux en route to the Moon as well as in lunar orbit. An impact probe carrying a mass spectrometer will also be a part of the spacecraft. The 1 ton class spacecraft will be launched by using a variant of flight proven indigenous Polar Satellite Launch Vehicle (PSLV-XL). The spacecraft will be finally placed in a 100 km circular polar orbit around the Moon with a planned mission life of two years.  相似文献   

9.
10.
A developed method of determination of orbital parameters allows one to estimate, along with orbit elements, some additional parameters that characterize solar radiation pressure and perturbing accelerations due to unloadings of reactiion wheels. A parameterized model of perturbing action of solar radiation pressure on the spacecraft motion is described (this model takes into account the shape, reflecting properties of surfaces, and spacecraft attitude). Some orbit determination results are presented obtained by the joint processing of radio measurements of slant range and Doppler, laser range measurements used to calibrate the radio measurements, optical observations of right ascension and declination, and telemetry data on spacecraft thrusters’ firings during an unloading of reaction wheels.  相似文献   

11.
12.
Reduction of flight duration after insertion till docking to the ISS is considered. In the beginning of the human flight era both the USSR and the USA used short mission profiles due to limited life support resources. A rendezvous during these missions was usually achieved in 1–5 revolutions. The short-term rendezvous were made possible by the coordinated launch profiles of both rendezvousing spacecraft, which provided specific relative position of the spacecraft or phase angle conditions. After the beginning of regular flights to the orbital stations these requirements became difficult to fulfill. That is why it was decided to transfer to 1- or 2-day rendezvous profile. The long stay of a crew in a limited habitation volume of the Soyuz-TMA spacecraft before docking to the ISS is one of the most strained parts of the flight and naturally cosmonauts wish to dock to the ISS as soon as possible. As a result of previous studies the short four-burn rendezvous mission profile with docking in a few orbits was developed. It is shown that the current capabilities of the Soyuz-FG launch vehicle and the Soyuz-TMA spacecraft are sufficient to provide for that. The first test of the short rendezvous mission during Progress cargo vehicle flight to the ISS is planned for 2012. Possible contingencies pertinent to this profile are described. In particular, in the majority of the emergency cases there is a possibility of an urgent transfer to the present 2-day rendezvous profile. Thus, the short mission will be very flexible and will not influence the ISS mission plan. Fuel consumption for the nominal and emergency cases is defined by statistical simulation of the rendezvous mission. The qualitative analysis of the short-term and current 2-day rendezvous missions is performed.  相似文献   

13.
14.
While much of what is known about the performance of spacecraft in flight is learned by monitoring telemetry data streams, this paper describes some unique observations made with ground-based astronomical equipment, done in conjunction with the tenth flight of the U.S. Space Shuttle. The study had two main objectives: to test the ability of low-cost, low-light-level television equipment to monitor satellites in orbit, and to attempt visual and photographic observation of the reentry characteristics of a Space Shuttle Orbiter. Both efforts met with considerable success and are described herein.  相似文献   

15.
16.
Belingheri M  Mirra C 《Acta Astronautica》2003,53(4-10):651-657
ESA astronauts' ISS flight opportunities are considered as a vital source to meet the utilisation, operation and political objectives that Europe has established for participating in the International Space Station programme. Recent internal ESA assessments have demonstrated that a rate of three flights per year for European Astronauts should be maintained as a minimum objective. The current flight rate is lower than this. In order to improve this situation, in the context of the activation of the ESA ISS Commercialisation programme, ESA is developing the conditions for the establishment of commercially based human spaceflights with the financial support of both ESA and the private sector or, in the future, only the latter. ESA is working in a Partnership with the space industry to facilitate the implementation of such projects and support customers with a range of end-to-end commercial services. The opportunities and challenges of a "commercial human spaceflight", involving a member of the European Astronaut Corps, or a privately employed flight participant, are discussed here.  相似文献   

17.
The European Space Agency (ESA) has decided to carry out a fly-by mission to the comet Halley. The spacecraft will be launched by an ARIANE II and intercept the retrograde Halley orbit on 13 March, 1986. One group of experiments is designed to obtain data on size, mass and composition of the dust in the cometary tail. Because of the very high relative velocity during fly-by (69 km/s) laboratory experiments are necessary to develop and calibrate the experiments. These experiments are presently under way in the laboratory of the Lehrstuhl für Raumfahrttechnik of the Technische Universität München. First results have been obtained for both the Dust Impact Detection System (DIDSY) and the P?articulate Impact Analyzer (PIA). These results are compared with the theoretical models for hypervelocity impact craters. The agreement is good at impact velocities around 15 km/s.  相似文献   

18.
Among the configurations of superconducting magnet structures proposed for protecting manned spaceships or manned deep space bases from ionizing radiation, toroidal ones are the most appealing for the efficient use of the magnetic field, being most of the incoming particle directions perpendicular to the induction lines of the field. The parameters of the toroid configuration essentially depend from the shape and volume of the habitat to be protected and the level of protection to be guaranteed. Two options are considered: (1) the magnetic system forming with the habitat a unique complex (compact toroid) to be launched as one piece; (2) the magnetic system to be launched separately from the habitat and assembled around it in space (large toroid).  相似文献   

19.
G. G. Reibaldi   《Acta Astronautica》2003,53(12):997-1000
The governments’ priority and budgets for space activities are steadily decreasing and the importance of space activities is not any longer reaching the front pages of the newspaper, as in the 1960s. On the other hand in Europe the people, at large, have shown an important interest and support for space activities. A contribution to bridge the gap between decreasing funding and important support of citizen can come from teaching space policy in universities as well as in special workshops for government, industrial and military circles. The paper will outline a course that fulfils this goal.  相似文献   

20.
Three orders of arguments are outlined to illustrate the importance of small missions. First, the classical reasons (one has to begin small, educational aspects, introduction to the space field) are summarized; then some thoughts are introduced on the efficacy and the efficiency of the effort invested (how expensive is a national project, and how advantageous the inevitable multinational cooperation); finally, a synopsis of the considerations about the need for cultural changes in the space program (the challenge of the coming era, the resulting needs, the philosophy of “small missions” and its contributions) is given.  相似文献   

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