Legal consequences of a SETI detection

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.     

An international relations perspective on the consequences of SETI

Can we envision what the laws of politics and the laws of ethics will be in extraterrestrial civilizations? The laws of physics and chemistry will be the same. Presumably, if there are biospheres in other solar systems, the nature of biology will be the same. Over time evolution may produce the same forms of consciousness and intelligence as we see on earth. However, the political and ethical systems on earth are diverse. Often our images of extraterrestrial civilizations are mere projections of earthly patterns of conflict and cooperation. Perhaps over time the many civilizations and patterns on earth will evolve into one global civilization with harmonious political and ethical norms. These may be the same in universal civilizations if evolution is a cosmic process.     

VLSI processors for signal detection in SETI

The objective of the Search for Extraterrestrial Intelligence (SETI) is to locate an artificially created signal coming from a distant star. This is done in two steps: (1) spectral analysis of an incoming radio frequency band, and (2) pattern detection for narrow-band signals. Both steps are computationally expensive and require the development of specially designed computer architectures. To reduce the size and cost of the SETI signal detection machine, two custom VLSI chips are under development. The first chip, the SETI DSP Engine, is used in the spectrum analyzer and is specially designed to compute Discrete Fourier Transforms (DFTs). It is a high-speed arithmetic processor that has two adders, one multiplier-accumulator, and three four-port memories. The second chip is a new type of Content-Addressable Memory. It is the heart of an associative processor that is used for pattern detection. Both chips incorporate many innovative circuits and architectural features.     

Short-pulse SETI

While most optical SETI experiments are configured to detect nanosecond pulses, the majority of their counterpart radio searches integrate for seconds to minutes, looking for unchanging narrow-band carriers or slowly pulsed modulation. The former approach is suggested as an effective way to stand out against stellar photon noise, while the latter approach is dictated by the dispersive effects of the interstellar medium as well as the high visibility of narrow-band signal components.In this paper, we consider effective signal strategies for those that produce, rather than simply search for, optical and radio beacons—signals that are designed to elicit responses from technological civilizations. By considering the communication problem from the point of view of the transmitters, rather than the receivers, we deduce some likely signal characteristics for beacons, and concommitant new strategies for SETI.     

SETI target selection

The NASA High Resolution Microwave Survey consists of two complementary elements: a Sky Survey of the entire sky to a moderate level of sensitivity; and a Targeted Search of nearby stars, one at a time, to a much deeper level of sensitivity. In this paper we propose strategies for target selection. We have two goals: to improve the chances of successful detection of signals from technical civilizations that inhabit planets around solar-type stars, and to minimize the chances of missing signals from unexpected sites. For the main Targeted Search survey of approximately 1000 nearby solar-type stars, we argue that the selection criteria should be heavily biased by what we know about the origin and evolution of life here on Earth. We propose that observations of stars with stellar companions orbiting near the habitable zone should be de-emphasized, because such companions would prevent the formation of habitable planets. We also propose that observations of stars younger than about three billion years should be de-emphasized in favor of older stars, because our own technical civilization took longer than three billion years to evolve here on Earth. To provide the information needed for the preparation of specific target lists, we have undertaken an inventory of a large sample of solar-type stars out to a distance of 60 pc, with the goal of characterizing the relevant astrophysical properties of these stars, especially their ages and companionship. To complement the main survey, we propose that a modest sample of the nearest stars should be observed without any selection biases whatsoever. Finally, we argue that efforts to identify stars with planetary systems should be expanded. If found, such systems should receive intensive scrutiny.     

Efficiency in SETI

While modern SETI experiments are often highly sensitive, reaching detection limits of 10^?25 W/m² Hz in the radio, interstellar distances imply that if extraterrestrial societies are using isotropic or broad-beamed transmitters, the power requirements for their emissions are enormous. Indeed, isotropic transmissions to the entire Galaxy, sufficiently intense to be detectable by our current searches, would consume power comparable to the stellar insolation of an Earth-size planet.In this paper we consider how knowledge can be traded for power, and how, and to what degree, astronomical accuracy can reduce the energy costs of a comprehensive transmission program by putative extraterrestrials. Indeed, an exploration of how far this trade-off might be taken suggests that extraterrestrial transmitting strategies of civilizations only modestly more advanced than our own would be, as are our SETI receiving experiments, inexpensive enough to allow multiple efforts. We explore the consequences this supposition has for our SETI listening experiments.     

SETI via Wormholes

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.     

The SERENDIP SETI project: new instrumentation for SETI and results of recent observations

Over the past 30 years research into the existence of extraterrestrial life has focused on attempts to detect stable narrowband radio signals emitted in the microwave portion of the radio frequency (RF) spectrum. The SERENDIP SETI group is currently conducting search operations on the world’s largest radio telescope at the Arecibo Observatory in Puerto Rico.The third generation SERENDIP system, SERENDIP III, is a 4 million channel FFT-based spectrum analyzer with 0.6 Hz frequency resolution. In this paper, we will discuss the results of our recent 3.5 year sky survey. SERENDIP looked at 95% of the sky visible from Arecibo in the 424–436 MHz range, analyzed 10¹⁴ spectral bins, and logged information on over 2.5×10⁸ signals.The fourth generation SERENDIP system expands on the SERENDIP III design. SERENDIP IV computes 2×10¹¹ operations each second, providing spectral analysis on 160 million channels in 1.7 s. We will discuss the design and use of the SERENDIP IV system and future observing plans.     

Space missions for SETI.

Radio Telescopes for SETI searches are less demanding than general purpose astronomical radio telescopes. This provides an opportunity to exploit economical approaches in designing SETI systems. Radio Telescopes in low Earth orbit offer no discernible advantages to SETI; indeed, they probably would perform more poorly than a telescope in any other location. Telescopes in geosynchronous orbits would be sufficiently far from Earth to mitigate greatly the deleterious effect of human radio transmissions. Telescopes on the far side of the moon would be superb both from a radio interference standpoint, and from a civil engineering standpoint. Single-reflector telescopes as large as 50 kilometers in diameter could be constructed with conventional materials. However, their costs appear prohibitive. The asteroid belt and the outer solar system are unpromising places to place a large radio telescope. Perhaps the ultimate radio telescope would utilize the sun as a gravitational lens, focusing radiation on free-flying 10-meter class or possibly larger radio telescopes located at distances of the order of 1000 A.U. from the sun. Such a combination has an energy collecting area at 10 centimeters wavelength equivalent to that of a radio telescope about 11 kilometers in diameter, or of the order of 3000 Arecibo radio telescopes. Such a system could detect transmitters with EIRP of the order of a gigawatt at a distance of the order of the distance to the galactic center.     

A SETI metapolicy: New directions towards comprehensive policies concerning the detection of extraterrestrial intelligence

At present we have only one agreed public policy for handling the detection of an extraterrestrial intelligence (ETI), the ‘First SETI Protocol’ of 1989, which guides action in the immediate aftermath of detection, even though SETI (the Search for Extraterrestrial Intelligence) constitutes an active search for such a detection. The purpose of this paper is to set out areas in which policies might fruitfully be developed, including reviewing the rationale and investment in SETI, handling ETI artefacts, and approaches to direct contact. ‘Negative’ possibilities will be examined, for example, whether an ETI artefact or data should be purposefully destroyed.     

SETI at the Nancay radiotelescope

The Nancay (France) radiotelescope has been used in June, 1981, to search for artificial monochromatic signals from 102 nearby stars, without success. A different approach to SETI is also considered based on the properties of wide band signals. A detection procedure, through Karhunen-Loeve analysis, is suggested.     

The SERENDIP piggyback SETI project

The SERENDIP project is an ongoing program of monitoring and processing broadband radio signals acquired by existing radio astronomy observatories. SERENDIP operates in a piggyback mode: it makes use of whatever observing plan (sequence of frequencies, sky coordinates, and polarizations) is under way at its host observatory. Moreover, the SERENDIP data acquisition system, once installed, operates autonomously. This approach makes it possible to obtain large amounts of high quality observing time in a manner that is economical and that does not adversely affect ongoing radio astronomy survey work. The SERENDIP II system has been installed at the NRAO 300-foot telescope at Green Bank, West Virginia, and has operated there for several thousand hours. In this report, we summarize our findings from these observations and describe the present status of the project. Two key elements of SERENDIP are the automated data acquisition system that uses adaptive thresholds and logs only statistically significant peaks in the real-time power spectra, and the subsequent off-line analysis programs that identify and reject a variety of interference signals. Several specific correlations have been identified that offer promise. At present, the development and testing of these interference rejection algorithms is the main thrust of our work.     

Recent SETI observations at Arecibo

During 1980 and 1981, the 305-m radio telescope at the Arecibo Observatory in Puerto Rico was used to conduct a high resolution search for narrowband signals from the direction of 210 nearby solar type stars and 5 OH masers. For each star at least 4 MHz of bandwidth surrounding the 21-cm HI line and/or the 18-cm OH lines was studied with a spectral resolution of 5.5 Hz in both right and left circular polarization. The formal limit of sensitivity achieved during the course of this search varied depending upon the particular receivers available. In all cases the search could have detected a narrowband transmitter of power comparable to the Arecibo planetary radar, had any such been transmitting on the frequencies searched during the time of observation out to the distance of the farthest target star. As in previous searches, the number of "false alarms" encountered was far greater than predicted on the basis of Gaussian noise statistics. A small number of stars have exhibited signals which cannot immediately be explained in terms of astrophysical or man-made sources and deserve reobservation. This is typical of the results of previous non-real-time searches and does not yet constitute the detection of an ETI.     

SETI education programs in Australia

This paper discusses and evaluates two innovative SETI education programs conducted at the University of Western Sydney, viz: the SETI Pathways Program and the Life in the Universe Curriculum Project.     

Preferred frequencies for SETI observations

SETI observational programs conducted over the last two decades, and most of those planned for the near future, have concentrated on searching for signals at microwave frequencies. Considerations of signal-to-noise ratio at the receiving end indicate that this is the correct approach if the broadcasting society is not concerned with directionality and transmits into a fairly large solid angle. However, if that society desires to transmit only a highly directional beacon, then it is not now possible, given our lack of knowledge of advanced space technology, to predict reliably whether microwave or infrared wavelengths are to be preferred in an optimum search program. Given the realities of current terrestrial technology, either the centimeter or millimeter domain is to be preferred to the infrared, independent of considerations of directionality. In any event, there does not appear to be any cosmically unique (“magic”) frequency at which to conduct SETI.     

Risk and value analysis of SETI

This paper attempts to apply a traditional risk and value analysis to the Search for Extraterrestrial Intelligence--SETI. In view of the difficulties of assessing the probability of success, a comparison is made between SETI and a previous search for extraterrestrial life, the biological component of Project Viking. Our application of simple Utility Theory, given some reasonable assumptions, suggests that SETI is at least as worthwhile as the biological experiment on Viking.     

Media reaction to a SETI success

Consideration of the reaction to a SETI detection by the media, and the effect this will have on the public, is more than mere sociological speculation. An accurate forecast of the media's interest can lead to actions that will help ensure that correct and comprehensible information reaches the public. This is most critical in the first few weeks following a discovery. While a widely accepted protocol for dealing with a detection exists in the "Declaration of Principles Following the Detection of Extraterrestrial Intelligence," it gives scant consideration to the fact that the actual situation will be chaotic and not subject to easy control. The 1996 story about the possible discovery of martian microfossils has provided a useful precedent for what will happen if astronomers uncover the existence of alien intelligence.     

SETI in the light of cosmic convergent evolution

Theodosius Dobzhansky, one of the founding fathers of the modern evolutionary synthesis, once famously stated that “nothing makes sense in biology except in the light of evolution”. Here it will be argued that nothing in astrobiology makes sense except in the light of “Cosmic Convergent Evolution” (CCE). This view of life contends that natural selection is a universal force of nature that leads to the emergence of similarly adapted life forms in analogous planetary biospheres. Although SETI historically preceded the rise of astrobiology that we have witnessed in the recent decade, one of its main tenets from the beginning was the convergence of life on a cosmic scale toward intelligent behavior and subsequent communication via technological means. The question of cultural convergence in terms of symbolic exchange, language and scientific capabilities between advanced interstellar civilizations has been the subject of ongoing debate. However, at the core of the search for extraterrestrial intelligence lies in essence a biological problem since even post-biological extraterrestrial intelligences must have had an origin based on self-replicating biopolymers. Thus, SETI assumes a propensity of the Universe towards biogenesis in accordance with CCE, a new evolutionary concept which posits the multiple emergence of life across the Cosmos. Consequently, we have to wonder about the biophilic properties the Universe apparently exhibits, as well as to try to find an encompassing theory that is able to explain this “fine-tuning” in naturalistic terms. The aims of this paper are as follows: 1) to emphasize the importance of convergent evolution in astrobiology and ongoing SETI research; 2) to introduce novel and biology-centered cosmological ideas such as the “Selfish Biocosm Hypothesis” and the “Evo Devo Universe” as valuable arguments in theorizing about the origin and nature of extraterrestrial intelligence and 3) to synthesize these findings within an emerging post-biological paradigm on which future SETI efforts may be founded.