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1.
“Mars Direct”, is an approach to the space Exploration Initiative that allows for the rapid initiation of manned Mars exploration, possibly as early as 1999. The approach does not require any on-orbit assembly or refueling or any support from the Space Station or other orbital infrastructure. Furthermore, the Mars Direct plan is not merely a “flags and footprints” one-shot expedition, but puts into place immediately an economical method of Earth-Mars transportation, real surface exploratory mobility, and significant base capabilities that can evolve into a mostly self-sufficient Mars settlement. This paper presents both the initial and evolutionary phases of the Mars Direct plan. In the initial phase, only chemical propulsion is used, sendig 4 persons on conjunction class Mars exploratory missions. Two heavy lift booster launches are required to support each mission. The first launch delivers an unfueled Earth Return Vehicle (ERV) to the martian surface, where it fills itself with methane/oxygen bipropellant manufactured primarily out of indigenous resources. After propellant production is completed, a second launch delivers the crew to the prepared site, where they conduct regional exploration for 1.5 years and then return directly to Earth in the ERV. In the second phase of Mars Direct, nuclear thermal propulsion is used to cut crew transit times in half, increase cargo delivery capacity, and to create the potential for true global mobility through the use of CO2 propelled ballistic hopping vehicles (“NIMFs”). In this paper we present both phases of the Mars Direct plan, including mission architecture, vehicle designs, and exploratory strategy leading to the establishment of a 48 person permanent Mars base. Some speculative thoughts on the possibility of actually colonizing Mars are also presented.  相似文献   

2.
When US President George W. Bush on 14 January 2004 announced a new US “Vision for Space Exploration”, he called for international participation in “a journey, not a race”, a call received with skepticism and concern elsewhere. But, after a slow start in implementing this directive, during 2006 NASA has increased the forward momentum of action on the program and of discussions on international cooperation in exploring “the Moon, Mars, and beyond”. There are nevertheless a number of significant top-level issues that must be addressed if a cooperative approach to human space exploration is to be pursued. These include the relationship between utilization of the ISS and the lunar exploration plans, integration of potential partners’ current and future capabilities into the exploration plans, and the evolving space-related intentions of other countries.  相似文献   

3.
Present operational space telecommunication systems are based on simultaneous availability of more than one satellite on orbit, mainly a spare satellite in addition to the operational one.Considering the costs associated to the delivery of extra flight models and to extra launchers, the question is asked whether it would not be advantageous to launch a very limited number of “overredundant” spacecraft instead of several standard satellites.The paper gives main conditions of reliability, size and redundancy concept under which an “overredundant” spacecraft could be a competitive approach to future operational systems.  相似文献   

4.
The Finnish officer and mathematician E. E. Neovius published, in 1875, a booklet in which he proposed a method to contact the inhabitans of Mars, using light signals projected to Mars with huge beacons. He constructed a message where the meaning of signals gradually rises from arithmetical concepts to logic and physics of the Solar System. The book was translated to French and Russian, but was forgotten when more sceptical attitudes replaced the optimistic views of intelligent life on Mars. Neovius’ philosophy of interplanetary communication relied upon ideas current in the 19th century. A “principle of analogy” seemed to guarantee the existence of planetary systems around the stars, and these planets must be inhabited like the Earth. Moreover, intelligence, knowledge and even science must be similar in the whole universe, whence no fundamental obstacle prevents a mutual understanding. In both respects, Neovius’ optimism has been replaced with more critical views.  相似文献   

5.
Investigations of blood pressure, heart rate (HR), and heart rate variability (HRV) during long term space flights on board the “ISS” have shown characteristic changes of autonomic cardiovascular control. Therefore, alterations of the autonomic nervous system occurring during spaceflight may be responsible for in- and post-flight disturbances. The device “Pneumocard” was developed to further investigate autonomic cardiovascular and respiratory function aboard the ISS. The hard-software diagnostic complex “Pneumocard” was used during in-flight experiment aboard ISS for autonomic function testing. ECG, photoplethysmography, respiration, transthoracic bioimpedance and seismocardiography were assessed in one male cosmonaut (flight lengths six month). Recordings were made prior to the flight, late during flight, and post-flight during spontaneous respiration and controlled respiration at different rates.HR remained stable during flight. The values were comparable to supine measurements on earth. Respiratory frequency and blood pressure decreased during flight. Post flight HR and BP values increased compared to in-flight data exceeding pre-flight values. Cardiac time intervals did not change dramatically during flight. Pulse wave transit time decreased during flight. The maximum of the first time derivative of the impedance cardiogram, which is highly correlated with stroke volume was not reduced in-flight.Our results demonstrate that autonomic function testing aboard the ISS using “Pneumocard” is feasible and generates data of good quality. Despite the decrease in BP, pulse wave transit time was found reduced in space as shown earlier. However, cardiac output did not decrease profoundly in the investigated cosmonaut.Autonomic testing during space flight detects individual changes in cardiovascular control and may add important information to standard medical control. The recent plans to support a flight to Mars, makes these kinds of observations all the more relevant and compelling.  相似文献   

6.
The considerable evidence that Mars once had a wetter, more clement, environment motivates the search for past or present life on that planet. This evidence also suggests the possibility of restoring habitable conditions on Mars. While the total amounts of the key molecules--carbon dioxide, water, and nitrogen--needed for creating a biosphere on Mars are unknown, estimates suggest that there may be enough in the subsurface. Super greenhouse gases, in particular, perfluorocarbons, are currently the most effective and practical way to warm Mars and thicken its atmosphere so that liquid water is stable on the surface. This process could take approximately 100 years. If enough carbon dioxide is frozen in the South Polar Cap and absorbed in the regolith, the resulting thick and warm carbon dioxide atmosphere could support many types of microorganisms, plants, and invertebrates. If a planet-wide martian biosphere converted carbon dioxide into oxygen with an average efficiency equal to that for Earth's biosphere, it would take > 100,000 years to create Earth-like oxygen levels. Ethical issues associated with bringing life to Mars center on the possibility of indigenous martian life and the relative value of a planet with or without a global biosphere.  相似文献   

7.
The X-38 Project forms part of the “X” prototype vehicle family developed by the United States. Its development was initiated by NASA to prepare the Crew Return Vehicle (CRV). The European participation in the X-38 Program has been significantly extended since the start of the X-38 cooperation in 1997 and is realized by ESA's “Applied Reentry Technology Program” and the German/DLR “Technologies for Future Space Transportation Systems” (TETRA) Project. European contributions to the X-38 Vehicle 201, (V-201) can be found in all technical key areas. The orbital flight and reentry with the X-38 V-201 will conclude the X-38 project in 2002.The CRV will be used from about mid-2005 as ’ambulance‘, ’lifeboat‘ or as alternate return vehicle for the crew of the International Space Station. Recognizing the very productive and mutually beneficial cooperation established on X-38, NASA and ESA have decided to continue this cooperation into the development of the operational CRV. The Phase C/D will be completed shortly after the Critical Design Review, scheduled for August 2002. The CRV production phase will start in October 2002 and will cover production of four CRV vehicles, ending in 2006.Based on the objective to identify a further evolution potential of the CRV towards a Crew Cargo Transfer Vehicle (CCTV), NASA has implemented upgrade studies in the CRV Phase C/D.  相似文献   

8.
The new-born bioscience called Nanobiology has tackled the problems of the possibility of existence of extraterrestrial life and intelligence and of biosystem distribution in the Universe, as such questions actually belong to the realm of Theoretical Biology. The central, and yet unanswered points of such science have been reinvestigated by attempting knowledge and control of the hard-to-determine nanoscale-level classical and quantum interactions, which would supposedly give mechanistic, definite answers, both informationally and energetically, to the vexing questions put by biosystems to science: is the “living state” a physically definible concept, and how to define it? Are nanoscale kinetics or even detailed mechanics involved in the origin of life? What about intelligence, consciousness and their nanophysical roots? Are “life” and “intelligence” engineerable properties, or is any Artificial Intelligence program bound to mere metaphors? Self-organization, studied at the thermodynamic and the hydrodynamic level, showed the possibility of chemical evolution from amino acids, probably of cometary and/or meteoritic origin, up to spatiotemporal organization, autopoiesis and biological evolution, but didn't explain the origins of life. Questioning the uniqueness of the earthly evolutionary chemistry is cardinal for the ETI dilemma, as from a budgetary appraisal of perspectives in bionanoscale chaotic undecidable dynamics, quantum gravity and quantum vacuum, both “living state” and “intelligence” look like nonlocal, spacetime-linked cosmic phenomena.  相似文献   

9.
Magnetism, iron minerals, and life on Mars   总被引:1,自引:0,他引:1  
A short critical review is provided on two questions linking magnetism and possible early life on Mars: (1) Did Mars have an Earth-like internal magnetic field, and, if so, during which period and was it a requisite for life? (2) Is there a connection between iron minerals in the martian regolith and life? We also discuss the possible astrobiological implications of magnetic measurements at the surface of Mars using two proposed instruments. A magnetic remanence device based on magnetic field measurements can be used to identify Noachian age rocks and lightning impacts. A contact magnetic susceptibility probe can be used to investigate weathering rinds on martian rocks and identify meteorites among the small regolith rocks. Both materials are considered possible specific niches for microorganisms and, thus, potential astrobiological targets. Experimental results on analogues are presented to support the suitability of such in situ measurements.  相似文献   

10.
Jones EG  Lineweaver CH  Clarke JD 《Astrobiology》2011,11(10):1017-1033
We present a comprehensive model of martian pressure-temperature (P-T) phase space and compare it with that of Earth. Martian P-T conditions compatible with liquid water extend to a depth of ~310?km. We use our phase space model of Mars and of terrestrial life to estimate the depths and extent of the water on Mars that is habitable for terrestrial life. We find an extensive overlap between inhabited terrestrial phase space and martian phase space. The lower martian surface temperatures and shallower martian geotherm suggest that, if there is a hot deep biosphere on Mars, it could extend 7 times deeper than the ~5?km depth of the hot deep terrestrial biosphere in the crust inhabited by hyperthermophilic chemolithotrophs. This corresponds to ~3.2% of the volume of present-day Mars being potentially habitable for terrestrial-like life.  相似文献   

11.
A powerful statistical tool, paired-comparison, was tested as a method to determine the relative value American people place on two possibly competing paradigms in the United States Space Program: “Space as a Place to Explore” and “Civil and Commercial Uses of Space”. A limitation of the results, but not the methodology, is the participants were college students, not “voting” adults. Reliability and validity of items were developed and tested in two studies suggesting that the paired-comparison method is a reliable and powerful tool for measuring the relative value the public may place on programs within the US Space Program.  相似文献   

12.
Kuznetz LH  Gan DC 《Astrobiology》2002,2(2):183-195
The recent discovery of high concentrations of hydrogen just below the surface of Mars' polar regions by Mars Odyssey has enlivened the debate about past or present life on Mars. The prevailing assumption prior to the discovery was that the liquid water essential for its existence is absent. That assumption was based largely on the calculation of heat and mass transfer coefficients or theoretical climate models. This research uses an experimental approach to determine the feasibility of liquid water under martian conditions, setting the stage for a more empirical approach to the question of life on Mars. Experiments were conducted in three parts: Liquid water's existence was confirmed by droplets observed under martian conditions in part 1; the evolution of frost melting on the surface of various rocks under martian conditions was observed in part 2; and the evaporation rate of water in Petri dishes under Mars-like conditions was determined and compared with the theoretical predictions of various investigators in part 3. The results led to the conclusion that liquid water can be stable for extended periods of time on the martian surface under present-day conditions.  相似文献   

13.
14.
Möhlmann D 《Astrobiology》2005,5(6):770-777
Mars Odyssey has given strong evidence for the existence of water in the upper martian surface at equatorial latitudes. The water content, which corresponds to the hydrogen in the soil, can regionally reach values up to about 15%. This water is mainly in the form of structurally and partially irreversibly bound "crystal" water, and of reversibly bound and partially unfrozen adsorption water. This adsorption water, which has "liquid-like" properties as a two dimensional fluid or film, can trigger-in the presence of ultraviolet light and in concentrations similar to what has been measured on Mars-photocatalytic processes that are important for martian surface chemistry. The consequences of the diurnally variable presence of adsorption water on the chemistry and hypothetical biological processes at and in the upper martian surface at equatorial and mid-latitudes are discussed in terms of water-related environmental aspects for chemical and hypothetical life processes on Mars.  相似文献   

15.
John C. Mankins   《Acta Astronautica》2009,65(9-10):1208-1215
Systems that depend upon the application of new technologies inevitably face three major challenges during development: performance, schedule and budget. Technology research and development (R&D) programs are typically advocated based on argument that these investments will substantially reduce the uncertainty in all three of these dimensions of project management. However, if early R&D is implemented poorly, then the new system developments that plan to employ the resulting advanced technologies will suffer from cost overruns, schedule delays and the steady erosion of initial performance objectives. It is often critical for senior management to be able to determine which of these two paths is more likely—and to respond accordingly. The challenge for system and technology managers is to be able to make clear, well-documented assessments of technology readiness and risks, and to do so at key points in the life cycle of the program.Several approaches have been used to evaluate technology maturity and risk in order to better anticipate later system development risks. The “technology readiness levels” (TRLs), developed by NASA, are one discipline-independent, programmatic figure of merit (FOM) that allows more effective assessment of, and communication regarding the maturity of new technologies. Another broadly used management tool is of the “risk matrix”, which depends upon a graphical representation of uncertainty and consequences. However, for the most part these various methodologies have had no explicit interrelationship.This paper will examine past uses of current methods to improve R&D outcomes and will highlight some of the limitations that can arise. In this context, a new concept for the integration of the TRL methodology, and the concept of the “risk matrix” will be described. The paper will conclude with observations concerning prospective future directions for the important new concept of integrated “technology readiness and risk assessments”.  相似文献   

16.
John C. Mankins   《Acta Astronautica》2009,65(9-10):1190-1195
The current emphasis in the US and internationally on lunar robotic missions is generally viewed as a precursor to possible future human missions to the Moon. As initially framed, the implementation of high level policies such as the US Vision for Space Exploration (VSE) might have been limited to either human lunar sortie missions, or to the testing at the Moon of concepts-of-operations and systems for eventual human missions to Mars [White House, Vision for Space Exploration, Washington, DC, 14 January, 2004. [1]]. However, recently announced (December 2006) US goals go much further: these plans now place at the center of future US—and perhaps international—human spaceflight activities a long-term commitment to an outpost on the Moon.Based on available documents, a human lunar outpost could be emplaced as early as the 2020–2025 timeframe, and would involve numerous novel systems, new technologies and unique operations requirements. As such, substantial investments in research and development (R&D) will be necessary prior to, during, and following the deployment of such an outpost. It seems possible that such an outpost will be an international endeavor, not just the undertaking of a single country—and the US has actively courted partners in the VSE. However, critical questions remain concerning an international lunar outpost. What might such an outpost accomplish? To what extent will “sustainability” be built into the outpost? And, most importantly, what will be the outpost's life cycle cost (LCC)?This paper will explore these issues with a view toward informing key policy and program decisions that must be made during the next several years. The paper will (1) describe a high-level analytical model of a modest lunar outpost, (2) examine (using this model) the parametric characteristics of the outpost in terms of the three critical questions indicated above, and (3) present rough estimates of the relationships of outpost goals and “sustainability” to LCC. The paper will also consider possible outpost requirements for near-term investments in enabling research in light of experiences in past advanced technology programs.  相似文献   

17.
In announcing a new Vision for the US space program, President George Bush committed the USA to “a long-term human and robotic program to explore the solar system”, via a return to the Moon, leading to exploration of Mars and other destinations. He also stated that other nations would be invited to join the vision. Many other nations have, or are developing, ‘exploration visions’ of their own. The potential for international cooperation therefore exists, both at the vision and program/project levels. This paper, based on Working Group discussions as part of an AIAA space cooperation workshop,1 presents an approach for maximizing the return on all global investments in space exploration. It proposes an international coordination mechanism through which all these various national activities could be integrated into an inherently global enterprise for space exploration, a ‘virtual program of programs’. Within the context of the coordination, individual activities would utilize the full range of cooperative mechanisms for implementation. A significant benefit of this mode of conducting cooperation is that it would not require the negotiation of complex overarching international agreements as a precondition for initiating international activity.  相似文献   

18.
We investigate a new mechanism for producing oxidants, especially hydrogen peroxide (H2O2), on Mars. Large-scale electrostatic fields generated by charged sand and dust in the martian dust devils and storms, as well as during normal saltation, can induce chemical changes near and above the surface of Mars. The most dramatic effect is found in the production of H2O2 whose atmospheric abundance in the "vapor" phase can exceed 200 times that produced by photochemistry alone. With large electric fields, H2O2 abundance gets large enough for condensation to occur, followed by precipitation out of the atmosphere. Large quantities of H2O2 would then be adsorbed into the regolith, either as solid H2O2 "dust" or as re-evaporated vapor if the solid does not survive as it diffuses from its production region close to the surface. We suggest that this H2O2, or another superoxide processed from it in the surface, may be responsible for scavenging organic material from Mars. The presence of H2O2 in the surface could also accelerate the loss of methane from the atmosphere, thus requiring a larger source for maintaining a steady-state abundance of methane on Mars. The surface oxidants, together with storm electric fields and the harmful ultraviolet radiation that readily passes through the thin martian atmosphere, are likely to render the surface of Mars inhospitable to life as we know it.  相似文献   

19.
If a detection of ETI takes place, this will in all probability be the result of either: (a) detecting and recognising a signal or other emission of ETI; or (b) the finding of an alien artifact (for instance on the Moon or other Celestial Body of our Solar System); or (c) the highly improbable event of an actual encounter. First and foremost, legal consequences regarding any of these contingencies will result from immediate consultations between nations on Earth. Understandings, memoranda and even agreements might be proposed and/or concluded. Such results within the field of terrestrial law will surely be a new branch of International Law, and particularly of International Space Law. At the same time, terrestrial nations will have to realize that any ETI will be self-determined intelligent individualities or organizations who might have their own understanding of “rules of behaviour” and thus, be legal subjects. Whether one calls such rules “law” or not: if two intelligent races—both of which have specific rules of behaviour—come into contact with each other, the basic understanding of such mutual rules will lead to a kind of “code of conduct”. This might be the starting point for a kind of Law—Metalaw—between different races in the Universe.  相似文献   

20.
While proposals for settling in the space frontier have appeared in the technical literature for over 20 years, it is in the case of Mars that the ethical dimensions of space settlement have been most studied. Mars raises the questions of the rights and wrongs of the enterprise more forcefully because: (a) Mars may possess a primitive biota; and (b) it may be possible to terraform Mars and transform the entire planet into a living world. The moral questions implicit in space settlement are examined below from the standpoints of four theories of environmental ethics: anthropocentrism, zoocentrism, ecocentrism and preservationism. In the absence of extraterrestrial life, only preservationism concludes that space settlement would be immoral if it was seen to be to the benefit of terrestrial life. Even if Mars is not sterile, protection for Martian life can be argued for either on intrinsic or instrumental grounds from the standpoints of all of these theories. It is argued further that a strict preservationist ethic is untenable as it assumes that human consciousness, creativity, culture and technology stand outside nature, rather than having been a product of natural selection. If Homo sapiens is the first spacefaring species to have evolved on Earth, space settlement would not involve acting ‘outside nature', but legitimately ‘within our nature'.  相似文献   

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