The search for extraterrestrial intelligence

  title={The search for extraterrestrial intelligence},
  author={Thomas L. Wilson},
As far as we know, humanity is alone in the Universe: there is no definite evidence for the existence of extraterrestrial life, let alone extraterrestrial civilizations (ETCs) capable of communicating or travelling over interstellar distances. Yet popular speculation about the existence of ETCs abounds, including reports of alien visitations either now or in the past. But there is a middle way. It is now possible to put limits on the existence of ETCs of varying capabilities, within arbitrary… 

Relative Likelihood of Success in the Search for Primitive versus Intelligent Extraterrestrial Life.

It is suggested that the search for extraterrestrial intelligence (SETI) may merit a federal funding level of at least $10 million per year, assuming that the average lifetime of technological species exceeds a millennium.

Signal coverage approach to the detection probability of hypothetical extraterrestrial emitters in the Milky Way

It is insisted that even if extraterrestrial civilizations do exist and communicate, the likelihood of detecting their signals crucially depends on whether the Earth lies within a region of the galaxy covered by such signals.

Eavesdropping on radio broadcasts from galactic civilizations with upcoming observatories for redshifted 21 cm radiation

The question of whether intelligent life exists elsewhere is one of the fundamental unknowns about our Universe. Over the past decade extra-solar planets have been discovered, providing new urgency

Who are the SETI sceptics

Impact of technological synchronicity on prospects for CETI

Abstract For over 50 years, astronomers have searched the skies for evidence of electromagnetic signals from extraterrestrial (ET) civilizations that have reached or surpassed our level of


The detection of signals from a possible extrasolar technological civilization is one of the most challenging efforts of science. In this work, we propose using natural telescopes made of single or

The astrobiological landscape : philosophical foundations of the study of cosmic life

Introduction Acknowledgements 1. Astrobiology: the colour out of space? 2. Cosmology, life, and duration of the past 3. Cosmology, life, and selection effects 4. Cosmology, life, and the archipelago

Should We Continue the Search

Since 1960, scientists have conducted more than 100 searches for signals from extraterrestrial civilizations.3 As of this writing, there has been no confirmed detection of alien technology; although


Detecting biosignatures, such as molecular oxygen in combination with a reducing gas, in the atmospheres of transiting exoplanets has been a major focus in the search for alien life. We point out

Empirical Evidence that the World Is Not a Computer

It is concluded that the world is a computing device and the discovery of empirical data sets that are algorithmically incompressible would therefore refute the hypothesis.



Searching for Extraterrestrial Civilizations

It is argued that planning for a search for extraterrestrial intelligence should involve a minimum number of assumptions and that the galaxy is either essentially empty with respect to technological civilizations or extensively colonized, and a SETI would be unproductive.

Beyond contact - a guide to SETI and communicating with alien civilizations

This introduction to searching for and communicating with intelligent life begins with some of the details behind UC Berkeleys groundbreaking, massively distributed SETI@home project, which processes intergalactic noise for pennies on the teraflop.

At what wavelengths should we search for signals from extraterrestrial intelligence?

  • C. Townes
  • Physics
    Proceedings of the National Academy of Sciences of the United States of America
  • 1983
While partially satisfying arguments may be given about optimal wavelengths for a search for signals from extraterrestrial intelligence, considerable uncertainty must remain.

Optimal wavelength region for communication with extraterrestrial intelligence: λ = 1.5 mm

This article shows that the best capability and reliability of communication at astronomical distances can be achieved at millimetre wavelengths. The cost of communication, and the number of

Six New Planets from the Keck Precision Velocity Survey

We report results of a search for planets around 530 main-sequence stars using the Keck HIRES spectrometer, which has provided Doppler precision of 3 m s-1 during the past 3 yr. We report six new

Eavesdropping: the radio signature of the Earth.

The case of planet earth is considered to understand better the information which might be derivable from radio leakage, and a model including over 2000 television transmitters is used to demonstrate the wealth of astronomical and cultural information available from a distant observer's careful monitoring of frequency and intensity variations in individual video carriers.

Radio Telescopes

  • J. Findlay
  • Physics
    IEEE Transactions on Military Electronics
  • 1964
A radio telescope is used in radio astronomy to measure the intensity of the radiation received from various parts of the sky. Such a telescope must be able both to detect and to locate faint radio

Rare Earth: Why Complex Life Is Uncommon in the Universe

Contents Preface to the Paperback Edition Preface to the First Edition Introduction: The Astrobiology Revolution and the Rare Earth Hypothesis Dead Zones of the Universe Rare Earth Factors 1 Why Life

The One-Hectare Telescope

The 1HT will be a large area telescope whose novel characteristics will be a wide field of view, continuous frequency coverage from .500 - 11 Ghz, multibeam capability, and provision for RFI

Searching for Interstellar Communications