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1.
The nature of a SETI search makes observations uniquely vulnerable to radio frequency interference because the frequency of a possible ETI signal is unknown. Sensitive radio telescopes, sophisticated software and enhanced signal detection equipment are employed to detect faint signals in the 1–3 GHz frequency range. Frequency management at SETI occurs within a policy environment of the ITU spectrum allocation process. Increased demand by commercial satellite services for access to spectrum adjacent to bandwidth allocated to radio astronomy creates severe international and domestic pressures on SETI observations. Strategies for addressing the RFI problem at the international level will be discussed that include a contingency ITU allocation plan for exclusive use of a particular frequency range by SETI in the event a signal is detected. The lunar farside is, by international agreement, a radio quiet zone for use by radio astronomers. Protected from most human-generated emissions, a SETI radio telescope array on the lunar farside would provide reliable data with minimum interference.  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.
During 16 weeks of continuous SETI observing at the Parkes Observatory in New South Wales, Australia, a set of time-averaged data with 643 Hz resolution were recorded and returned to the SETI Institute for post-processing. These data are the 14 second (10 frame) average powers in each of 15,552 “subband” channels covering 10 MHz of the spectrum in both right and left circular polarizations that were used by the signal detection hardware to baseline and threshold the 1 Hz high resolution SETI spectra. The observations covered frequencies from 1.2 to 3 GHz, tracking 209 stellar targets across the sky. The data at each frequency were averaged over all directions and then interrogated to attempt to determine the prevalence of radio frequency interference (RFI). Estimates were made for the probability of encountering RFI at a particular frequency. Particular attention has been paid to those portions of the spectrum that are allocated as primary use status, or footnote protection for radioastronomy. This sixteen-week snapshot of the RFI situation at Parkes is by now out of date. Unfortunately, a year later, the situation has undoubtedly worsened.  相似文献   

4.
The impact of confirmation of life outside the small ecosphere we call Earth will be profound on the terran population as a whole. The “Declaration Of Principles Concerning Activities Following The Detection Of Extraterrestrial Intelligence” and the IAA Position Paper “A Decision Process for Examining the Possibility of Sending Communications To Extraterrestrial Civilizations: A Proposal” provide a firm basis for the development of a new body of space law. It is important that space law design and prepare for implementation of a protocol to guide the nations of the world concerning the search for extraterrestrial intelligence (SETI), through the advice and cooperation of scientists, jurisprudential, philosophical, political and sociological scholars. Through the IAA, the IISL, the United Nations and other organizations, formal documentation should be drafted to encode the Declaration of Principles and IAA Position Paper referred to above. In this way, a body of metalaw can be developed to enable human communication with non-terrestrial life. This paper discusses the philosophical and sociological parameters of terran understanding of our place in the universe which will dramatically impact jurisprudential thought and action in light of the realization of the infinitesimally small niche that humankind occupies. A discussion of these interdisciplinary concerns will be necessary to realize a metalegal approach to interstellar communications and relations.  相似文献   

5.
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   

6.
David R. DeBoer   《Acta Astronautica》2006,59(12):1153-1159
The Allen telescope array (ATA) currently under construction affords the possibility of a dedicated and highly efficient SETI program that may be done commensally with other radio astronomy programs. This symbiosis is important in order to maintain and sustain the long-term effort that may be required in order to achieve success as a positive or null result. The technology that is being exploited is the construction of many small elements that allow large fields-of-view at high sensitivity, the use of ultra-wideband front-ends, and the use of flexible digital “intermediate frequency (IF)” systems. The project is under construction in phases, with the first 32 antennas expected to be functional in the fall of 2004, the next 173 dishes operational early 2006, with plans for 350 antennas total within this decade.  相似文献   

7.
This first of several study papers, based on a fundamental paper presented in 1972, provides an independent conceptual analysis and evaluation of the lunar environment as industrial base and habitat. A selenosphere system strategy is outlined. The underlying concept is that of one or several lunar industrial zones for resource extraction and on-surface processing, integrated with a circumlunar zero-g processing capability, serving markets in geolunar space. A classification of lunar elements by utilization category is presented. Lunar oxygen is a prime candidate for being an initial economic “drawing card”, because of its value for fast transportation in geolunar space, requiring significantly fewer ships for equal transfer capability per unit time than electric transports which, however, have value, especially between geosynchronous and lunar orbit. The reduced development difficulties of controlled fusion outside the atmosphere and its advantages for extracting oxygen and other elements in quantity are summarized. Examples of lunar cycle management as fundamental exoindustrial requirement for economic resource enhancement are presented. The principal initial socio-economic value of lunar industry lies in the use of lunar resources for exoindustrial products and operations designed to accelerate, intensify and diversify Earth-related benefits. In the longer run, lunar settlements are a highly suitable proving ground for studying and testing the complex matrix of technological, biological, cultural, social and psychological aspects that must be understood and manageable before large settlements beyond Earth can have a realistic basis for viability. The lunar environment is more suitable for experimentation and comparatively more “forgiving” in case of failures than is orbital space.  相似文献   

8.
The special theory of relativity rests on the assumption that in no case can the speed of light be exceeded. Rather surprisingly, however, recent advances in the general theory of relativity show that Faster-Than-Light (FTL) travel is allowed by Einstein’s gravitational theory. An explanation of this apparent contrast between special and general relativity lies in the fact that general relativity uses non-linear differential equations and non-Euclidean spacetime geometry that special relativity does not. Therefore, this larger mathematical armoury makes room for a whole new class of very subtle and unexpected relativistic phenomena to come to light. One of these is the Theory of Wormholes, more politely termed Tunnels into Space–Time. In 1988, Kip S. Thorne and Michael S. Morris published a path-breaking paper about Wormholes showing how spaceflight between two stars might be possible in a time of hours if a “tunnel” dug into space–time exists between them. However, they also showed that keeping the tunnel open for the spaceship to travel through would require a kind of matter, called “exotic” by them, that does not appear to exist in nature, because its tensional strength would have to exceed the energy density of its matter. This request is a severe constraint to the natural existence of Morris–Thorne Wormholes, or even to their artificial construction by an advanced civilization. In 1995, however, the present author sought to replace the exotic matter in a Morris–Thorne Wormhole by a very intense magnetic field. Such “Magnetic Wormholes” could indeed exist because very intense magnetic fields are already known to exist on the surface of neutron stars and pulsars. This paper discusses the consequences on SETI of the possible existence of Magnetic Wormholes. Phenomena of divergent gravitational lensing might possibly occur in the proximity of pulsars and neutron stars. These effects could help us detect signals from very far civilisations by virtue of ordinary SETI techniques already in use.  相似文献   

9.
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   

10.
Lunar base development missions   总被引:1,自引:0,他引:1  
On 20 July 1969, humankind first set foot on our Moon. Since then we have developed the Space Shuttle, explored most of the planets, cooperated in the development of the International Space Station, and expanded our knowledge of the universe through use of systems such as the Hubble Space Telescope and the Mars Pathfinder. After just five human follow-on missions to our Moon, we have returned robotically only twice to orbit, to map the surface and explore for resources.

The indication of the presence of hydrogen concentration at the poles of our Moon found by Lunar Prospector has added a new perspective for groups studying and implementing future lunar missions. Plans for nearterm missions such as the European Space Agency (ESA) “Euromoon 2000”, the Japanese Lunar A and Selene, and the Mitsubishi ”Earthrise 2001” Project, along with follow-on phases to the Lunar Prospector, are the beginning of humankind's return to the Moon. Organizations such as the International Academy of Astronautics have long championed the “Case for an International Lunar Base,” and a vision of a commercially-based lunar program has been outlined by several groups. A Lunar Economic Development Authority (LEDA) promoted by the United Society in Space was promulgated by the filing of articles of incorporation in the state of Colorado on 4 August 1997. This non-profit corporation has as its goal the orderly development of the Moon, through issuance of bonds to international private citizens and business entities who care to invest in its long-term development.

This paper draws from the works of the aforementioned, and specifically from the International Academy of Astronautics Lunar Base Committee, to structure a series of architectures leading toward eventual international commercial colonization of the lunar surface. While the prospect of fully reusable transportation systems utilizing fully developed lunar resources to perpetuate the permanent lunar infrastructure is enticing, this is a goal. We must utilize our current and near-term capabilities to re-initiate human lunar presence, and then build on emerging technologies to strengthen our capabilities. Humankind's return to the Moon is a part of our destiny. We can return in the near future, and then proceed to a commercial, permanent settlement in the 21st century.  相似文献   


11.
In the present paper (originally presented at the First IAA Symposium on Searching for Life Signatures hold at the UNESCO on 22–26 September 2008) I try to summarize the results of all my previous studies on active SETI and its possible dangers for us, also considering some new topics, in order to provide a possibly complete overview of the whole matter. First, I try to evaluate the possible risks of an indirect contact with aliens, from the social, cultural, and religious point of view; then, the possible risks related with receiving information about alien science and technology; finally, the risk that active SETI could increase the probability of a physical contact with hostile aliens. My conclusion is that active SETI is very unlikely to be dangerous for us, but, at present, such a possibility cannot be completely excluded. Surprisingly, it turns out that a very important point to be assessed in order to improve our evaluation of active SETI is the pace of our technological progress. Some suggestions about the policy that international community should adopt towards active SETI are also included.  相似文献   

12.
13.
Space at Surrey has developed over 25 years from very modest beginnings in 1974 to an international space centre by 1998. It has pioneered small satellites and succeeded in launching 14 low cost but sophisticated microsatellites over the course of two decades. In the 1990s, small satellites have become fashionable—but this was not always so! This paper describes the 25 years history of “Space at Surrey”.  相似文献   

14.
The Search for ExtraTerrestrial Intelligence (SETI) finally has its own full-time telescope. The Allen telescope array (ATA) in Northern California was dedicated on October 11, 2007. This array, which will eventually be composed of 350 small radio antennas, each 6.1 m in diameter, is being built as a partnership between the SETI Institute and the University of California Radio Astronomy Laboratory. Last October, Paul G. Allen (who provided the funds for the technology development and the first phase of array construction) pushed a silver button and all 42 antennas of the current ATA-42 slewed to point in the direction of the distant galaxy M81. Specialized electronic backend detectors attached to the ATA began making a radio map of that galaxy and simultaneously began SETI observations of HIP48573, a G5V star near M81 on the sky and a distance of 264 light years from Earth. The Allen telescope array will greatly improve the speed of conducting SETI searches over the next few decades, and it will allow a suite of different search strategies to be undertaken. This paper summarizes some of the earliest SETI observations from the array, and describes the search strategies currently being planned.  相似文献   

15.
The Search for Extraterrestrial Intelligence (SETI) has a low probability of success, but it would have a high impact if successful. Therefore it makes sense to widen the search as much as possible within the confines of the modest budget and limited resources currently available. To date, SETI has been dominated by the paradigm of seeking deliberately beamed radio messages.However, indirect evidence for extraterrestrial intelligence could come from any incontrovertible signatures of non-human technology. Existing searchable databases from astronomy, biology, earth and planetary sciences all offer low-cost opportunities to seek a footprint of extraterrestrial technology. In this paper we take as a case study one particular new and rapidly-expanding database: the photographic mapping of the Moon's surface by the Lunar Reconnaissance Orbiter (LRO) to 0.5 m resolution. Although there is only a tiny probability that alien technology would have left traces on the moon in the form of an artifact or surface modification of lunar features, this location has the virtue of being close, and of preserving traces for an immense duration.Systematic scrutiny of the LRO photographic images is being routinely conducted anyway for planetary science purposes, and this program could readily be expanded and outsourced at little extra cost to accommodate SETI goals, after the fashion of the SETI@home and Galaxy Zoo projects.  相似文献   

16.
17.
Tarter J 《Acta Astronautica》1997,41(4-10):613-622
Although there are no federally funded projects at this time, SETI (the search for extraterrestrial intelligence) is a vigorous exploratory science. There are currently eight observational programs on telescopes around the world, of which the Phoenix Project is the most comprehensive. Most of these projects are rooted in the conclusions of the pioneering studies of the early 1970's that are summarized in the Cyclops Report. Technology has experienced an exponential growth over the past two and a half decades. It is reasonable to reassess the Cyclops conclusions as SETI enters the next century. Listening for radio signals is still the preferred method of searching, however new technologies are making searches at other wavelengths possible and are modifying the ways in which the radio searches can and should be conducted. It may be economically feasible to undertake the construction of very large telescopes that can simultaneously provide multiple beams on the sky for use by SETI and the radioastronomy community.  相似文献   

18.
19.
When designing the radio-electronic equipment for long-term operation in a space environment, one of the most important problems is a correct estimation of radiation stability of its electric and radio components (ERC) against radiation-stimulated doze failures and one-particle effects (upsets). These problems are solved in this paper for the integrated microcircuits (IMC) of various types that are to be installed onboard the Fobos-Grunt spacecraft designed at the Federal State Unitary Enterprise “Lavochkin Research and Production Association.” The launching of this spacecraft is planned for 2009.__________Translated from Kosmicheskie Issledovaniya, Vol. 43, No. 3, 2005, pp. 237–239.Original Russian Text Copyright © 2005 by Kuznetsov, Popov, Khamidullina.  相似文献   

20.
Because the need for energy is global, and many energy networks are already interdependent, because no one country has sufficient technological capability or sufficient funds to provide a space solar powered solution on its own, and because any such solution will require international regulation, international coordination will be vital to any attempt to produce energy for Earth from space. This will be made easier by the fact that work on the subject has already been widely publicized and distributed and cooperative efforts have already been made. Various coordinating approaches are described and the need to forge partnerships between government, industry and academia — with greater involvement of all non-space groups concerned with energy — is emphasized. A “terracing approach” to the actual implementation of SPS is suggested and outlined.  相似文献   

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