FACTOID # 20: Statistically, Delaware bears more cost of the US Military than any other state.
 
 Home   Encyclopedia   Statistics   States A-Z   Flags   Maps   FAQ   About 
 
WHAT'S NEW
RELATED ARTICLES
People who viewed "SETI" also viewed:
 

SEARCH ALL

FACTS & STATISTICS    Advanced view

Search encyclopedia, statistics and forums:

 

 

(* = Graphable)

 

 


Encyclopedia > SETI
This article is about the search for extra-terrestrial intelligence. On other uses, see Seti.

SETI (Search for Extra-Terrestrial Intelligence) is the name for a number of organized efforts to detect Extraterrestrial life. A number of efforts with "SETI" have been organized, including projects funded by the United States Government. The general approach of SETI projects is to survey the sky to detect the existence of transmissions from a civilization on a distant planet, an approach widely endorsed by the scientific community as hard science (see, e.g., claims in Skeptical Inquirer [1]). Image File history File links Acap. ... This article is about the search for extra-terrestrial intelligence. ... “Green people” redirects here. ... The government of the United States, established by the United States Constitution, is a federal republic of 50 states, a few territories and some protectorates. ... A typical daytime sky. ... Interstellar communication is the transmission of signals across planetary systems. ... This article or section does not adequately cite its references or sources. ... It has been suggested that this article or section be merged with Pure science. ... The Skeptical Inquirer is a magazine of the Committee for the Scientific Investigation of Claims of the Paranormal (CSICOP) dedicated to debunking pseudoscience. ...


There are great challenges in searching across the sky for a first transmission that could be characterized as intelligent, since its direction, spectrum and method of communication are all unknown beforehand. SETI projects necessarily make assumptions to narrow the search, and thus no exhaustive search has so far been conducted. Many Discovery Science documentaries have featured SETI. Discovery Science (also known as Discovery-Based Science) is a scientific methodology which emphasizes analysis of large volumes of experimental data with the goal of finding new patterns or correlations, leading to hypothesis formation and other scientific methodologies. ...

Contents

Radio SETI experiments

Early work

In 1960, Cornell University astronomer Frank Drake performed the first modern SETI experiment, named "Project Ozma", after the Queen of Oz in L. Frank Baum's fantasy books. Drake used a 25-meter-diameter radio telescope at Green Bank, West Virginia, to examine the stars Tau Ceti and Epsilon Eridani near the 1.420 gigahertz marker frequency. A 400 kilohertz band was scanned around the marker frequency, using a single-channel receiver with a bandwidth of 100 hertz. The information was stored on tape for off-line analysis. He found nothing of great interest. Year 1960 (MCMLX) was a leap year starting on Friday (link will display full calendar) of the Gregorian calendar. ... Cornell University is a university located in Ithaca, New York, USA. Its two medical campuses are in New York City and Education City, Qatar. ... Professor Frank Drake Frank Drake (born May 28, 1930, Chicago, Illinois) is an American astronomer and astrophysicist. ... Project Ozma was a pioneering SETI experiment started in 1960 by Cornell University astronomer Frank Drake, at the National Radio Astronomy Observatory at Green Bank, West Virginia. ... Princess Ozma Princess Ozma is a fictional character in the Land of Oz universe created by L. Frank Baum. ... The Laughing Dragon of Oz, see Frank Joslyn Baum . ... Green Bank is located within Pocahontas County, West Virginia (Eastern Region), inside the Allegheny Mountain Range, and can be reached via Hwy 28. ... Tau Ceti (τ Cet / τ Ceti) is a star commonly mentioned by science fiction authors since it is similar to the Sun in mass and spectral type in addition to being relatively close to us. ... Epsilon Eridani (ε Eri / ε Eridani) is a notable main-sequence K2 class star in the constellation of Eridanus. ...


The first SETI conference took place at Green Bank in 1961. The Soviets took a strong interest in SETI during the 1960s and performed a number of searches with omnidirectional antennas in the hope of picking up powerful radio signals. TV host and American astronomer Carl Sagan and Soviet astronomer Iosif Shklovskii together wrote the pioneering book in the field, Intelligent Life in the Universe which was published in 1966 [2]. Soviet redirects here. ... The 1960s decade refers to the years from January 1, 1960 to December 31, 1969, inclusive. ... An omnidirectional antenna is an antenna system which radiates power uniformly in one plane with a directive pattern shape in a perpendicular plane. ... Insert non-formatted text here Carl Edward Sagan (November 9, 1934 – December 20, 1996) was an American astronomer and astrobiologist and a highly successful popularizer of astronomy, astrophysics, and other natural sciences. ... Iosif Samuilovich Shklovsky (Ио́сиф Самуи́лович Шкло́вский) (July 1, 1916 – March 3, 1985) was a Russian astronomer and astrophysicist. ... Year 1966 (MCMLXVI) was a common year starting on Saturday (link will display full calendar) of the 1966 Gregorian calendar. ...


In the March 1955 issue of Scientific American, Dr. John Kraus, Professor Emeritus and McDougal Professor of Electrical Engineering and Astronomy at the Ohio State University, described a concept to scan the cosmos for natural radio signals using a flat-plane radio telescope equipped with a parabolic reflector. Within two years, his concept was approved for construction by the Ohio State University. With $71,000 total in grants from the National Science Foundation, construction of the first Kraus-style radio telescope began on a 20-acre plot in Delaware, Ohio. The 360-feet wide, 500-feet long, and 70-feet high telescope was powered up in 1963. This Ohio State University radio telescope was called Big Ear. Later, it began the world's first continuous SETI program, called the Ohio State University SETI program. Year 1955 (MCMLV) was a common year starting on Saturday (link displays the 1955 Gregorian calendar). ... Scientific American is a popular-science magazine, published (first weekly and later monthly) since August 28, 1845, making it the oldest continuously published magazine in the United States. ... Electrical Engineers design power systems… … and complex electronic circuits. ... A giant Hubble mosaic of the Crab Nebula, a supernova remnant Astronomy (also frequently referred to as astrophysics) is the scientific study of celestial objects (such as stars, planets, comets, and galaxies) and phenomena that originate outside the Earths atmosphere (such as the cosmic background radiation). ... Ohio State University (OSU) is a coeducational public research university in the state of Ohio. ... The Ancient and Medieval cosmos as depicted in Peter Apians Cosmographia (Antwerp, 1539). ... The 64 meter radio telescope at Parkes Observatory A radio telescope is a form of directional radio antenna most often used in radio astronomy and in tracking and collecting data from satellites and space probes (see Deep Space Network), and are also used in the SETI project. ... A reflector can mean one of several things: a reflecting telescope a device or a part of an antenna that reflects radio waves a device that causes reflection, for example, a mirror or a retroreflector a 1981 album by Pablo Cruise In LAPACK the term reflector with the types block... The logo of the National Science Foundation The National Science Foundation (NSF) is an independent United States government agency that supports fundamental research and education in all the non-medical fields of science and engineering. ... The City of Delaware is located near the center of the state of Ohio, about 20 miles north of Columbus, Ohio. ... Year 1963 (MCMLXIII) was a common year starting on Tuesday (link will display full calendar) of the Gregorian calendar. ... The 64 meter radio telescope at Parkes Observatory A radio telescope is a form of directional radio antenna most often used in radio astronomy and in tracking and collecting data from satellites and space probes (see Deep Space Network), and are also used in the SETI project. ... The Big Ear was a radio telescope located on the grounds of the Ohio Wesleyan Universitys The Perkins Observatory from the 1960s to 1998 when it was disassembled. ...


In 1971, the U.S. National Aeronautics and Space Administration (NASA) funded a SETI study that involved Drake, Bernard Oliver of Hewlett-Packard Corporation, and others. The resulting report proposed the construction of an Earth-based radio telescope array with 1,500 dishes known as "Project Cyclops". The price tag for the Cyclops array was $10 billion USD. Cyclops was not built. Year 1971 (MCMLXXI) was a common year starting on Friday (link will display full calendar) of the 1971 Gregorian calendar. ... NASA Logo Listen to this article · (info) This audio file was created from the revision dated 2005-09-01, and does not reflect subsequent edits to the article. ... Bernard M. Oliver (1919-1995), (aka Barney Oliver) was an eminent scientist having made important contributions in many fields including Radar, Television, and Computers. ... The Hewlett-Packard Company (NYSE: HPQ), commonly known as HP, is a very large, global company headquartered in Palo Alto, California, United States. ... Project Cyclops was a 1971 NASA project that investigated SETI. The project team created a design for coordinating large numbers of radio telescopes to search for Earth-like radio signals at a distance of up to 1000 light-years to find intelligent life. ...

The WOW! Signal
Credit: The Ohio State University Radio Observatory and the North American Astrophysical Observatory (NAAPO).

Image File history File links Image of the WOW! signal File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ...

The "Wow!" signal

Main article: Wow! signal

The OSU SETI program gained fame on August 15, 1977 when Jerry Ehman, a project volunteer, witnessed a startlingly strong signal received by the telescope. He quickly circled the indication on a printout and scribbled the phrase “Wow!” in the margin. This signal, dubbed the Wow! signal, is considered by some to be the most likely candidate from an artificial, extraterrestrial source ever discovered, but it has not been detected again in several additional searches. The WOW! Signal Credit: The Ohio State University Radio Observatory and the North American AstroPhysical Observatory (NAAPO). ... Also: 1977 (album) by Ash. ... “Green people” redirects here. ...


Arecibo message

Main article: Arecibo message

In 1974, a largely symbolic attempt was made to send a message to other worlds. To celebrate a substantial upgrading of the 305 meter Arecibo Radio Telescope in Puerto Rico, a coded message of 1,679 bits was transmitted towards the Globular Cluster M13, about 25,100 light years away. The pattern of 0s and 1s contained in the message, when plotted, defines a two-dimensional 23 by 73 grid that reveals some data about our location in the Solar System, a stylized figure of a human being, chemical formulas, and an outline of the radio telescope itself. The 23 by 73 grid was chosen because both 23 and 73 are prime numbers, which makes it easier to decode the message. The reasons for this are: Arecibo Observatory This is the message with color added to highlight its separate parts. ... 1974 (MCMLXXIV) was a common year starting on Tuesday. ... The Arecibo Observatory is located in Arecibo, Puerto Rico on the north coast of the island. ... This article is about the unit of information. ... Messier Object 13, the Great Globular Cluster in Hercules; one of the most prominent and best known globular clusters of the Northern celestial hemisphere. ... Major features of the Solar System (not to scale; from left to right): Pluto, Neptune, Uranus, Saturn, Jupiter, the asteroid belt, the Sun, Mercury, Venus, Earth and its Moon, and Mars. ... In mathematics, a prime number (or a prime) is a natural number that has exactly two (distinct) natural number divisors, which are 1 and the prime number itself. ...

  • an attempt to factor the length of the message would show that it can't contain a grid with more than two dimensions (since there are just two factors);
  • assuming a two dimensional grid, there are only two possible resultant images, with dimensions 23x73 or 73x23.

Given the limitations of the speed of light for message transmission, no reply would be possible before the year 52,174 (approximately) and hence a crop circle known as the Arecibo reply has been dismissed by some as a publicity stunt[citation needed]. Controversy has also arisen as the transmission raised the serious question of whether such a small research group should be allowed to speak on Earth's behalf.[citation needed] A crop circle consisting of multiple circles. ... Arecibo reply crop circle The Arecibo reply was the name given to a crop circle that appeared in farmland next to the Chilbolton radio telescope; home to the Search for Extraterrestrial Intelligence Institute (SETI) in Hampshire, UK, on 19 August 2001. ... The media itself often stage stunts for movies and television shows. ...


SERENDIP

Main article: SERENDIP

In 1979 the University of California, Berkeley launched a SETI project named "Search for Extraterrestrial Radio Emissions from Nearby Developed Intelligent Populations (SERENDIP)" [3]. In 1986, UC Berkeley initiated their second SETI effort, SERENDIP II, and has continued with two more SERENDIP efforts to the present day. A new spectrometer named SERENDIP V is expected to be deployed in the near future. SERENDIP or Search for Extraterrestrial Radio Emissions from Nearby Developed Intelligent Populations is a UC Berkeley SETI Program. ... Also: 1979 by Smashing Pumpkins. ... Sather tower (the Campanile) looking out over the San Francisco Bay and Mount Tamalpais. ... SERENDIP or Search for Extraterrestrial Radio Emissions from Nearby Developed Intelligent Populations is a UC Berkeley SETI Program. ...


[email protected]

Main article: [email protected]

[email protected] is an extremely popular distributed computing project that was launched by U.C. Berkeley in May 1999, and is heavily sponsored by The Planetary Society. The project is run by director David Anderson and chief scientist Dan Werthimer. Any individual can become involved with SETI research by downloading and running the [email protected] software package, which then runs signal analysis on a "work unit" of data recorded from the central 2.5 MHz wide band of the SERENDIP IV instrument. The results are then automatically reported back to UC Berkeley. Over 5 million computer users in more than 200 countries have signed up for [email protected] and have collectively contributed over 19 billion hours of computer processing time. [4] [5] As of December 4, 2006 the [email protected] grid operates at 257 TeraFLOPS, making it equivalent to the second fastest supercomputer on Earth.[6] Radio source SHGb02+14a is the most interesting signal analyzed to date. [email protected] logo [email protected] (SETI at home) is a distributed computing project using Internet-connected computers, hosted by the Space Sciences Laboratory, at the University of California, Berkeley, in the United States. ... Image File history File links [email protected]_Logo. ... Image File history File links [email protected]_Logo. ... Distributed computing is a method of computer processing in which different parts of a program run simultaneously on two or more computers that are communicating with each other over a network. ... This article is in need of attention. ... David Anderson may refer to: David Anderson (Canadian politician) (born 1937), Canadian Liberal politician and former cabinet member David Anderson (bishop) (1814–1885) English Bishop. ... The NASA Columbia Supercomputer. ... December 4th redirects here. ... For the Manfred Mann album, see 2006 (album). ... ... The TOP500 project ranks and details the 500 most powerful publicly-known computer systems in the world. ... A supercomputer is a computer that led the world in terms of processing capacity, particularly speed of calculation, at the time of its introduction. ... 2 comparison graphs of the signal, from [email protected] [1] Radio source SHGb02+14a is a source and a candidate in the Search for Extra-Terrestrial Intelligence (SETI), discovered on March 2003 by [email protected] and announced in New Scientist on September 1, 2004. ...


Sentinel, META, and BETA

In 1980, Carl Sagan, Bruce Murray, and Louis Friedman founded the U.S. Planetary Society, partly as a vehicle for SETI studies. Year 1980 (MCMLXXX) was a leap year starting on Tuesday (link displays the 1980 Gregorian calendar). ... Insert non-formatted text here Carl Edward Sagan (November 9, 1934 – December 20, 1996) was an American astronomer and astrobiologist and a highly successful popularizer of astronomy, astrophysics, and other natural sciences. ... Born November 30, 1931 in New York, NY. Married to Suzanne Moss, 5 children. ... This article is in need of attention. ...


In the early 1980s, Harvard University physicist Paul Horowitz took the next step and proposed the design of a spectrum analyzer specifically intended to search for SETI transmissions. Traditional desktop spectrum analyzers were of little use for this job, as they sampled frequencies using banks of analog filters and so were restricted in the number of channels they could acquire. However, modern integrated-circuit digital signal processing (DSP) technology could be used to build autocorrelation receivers to check far more channels. This work led in 1981 to a portable spectrum analyzer named "Suitcase SETI" that had a capacity of 131,000 narrow band channels. After field tests that lasted into 1982, Suitcase SETI was put into use in 1983 with the 26-meter Harvard/Smithsonian radio telescope at Harvard, Massachusetts. This project was named "Sentinel", and continued into 1985. Harvard University (incorporated as The President and Fellows of Harvard College) is a private university in Cambridge, Massachusetts, USA and a member of the Ivy League. ... Paul Horowitz (born 1942) is a U.S. physicist and electrical engineer, known primarily for his work in electronics design, as well as for his role in the search for extra-terrestrial intelligence (see SETI). ... Digital signal processing (DSP) is the study of signals in a digital representation and the processing methods of these signals. ... A plot showing 100 random numbers with a hidden sine function, and an autocorrelation of the series on the bottom. ... Year 1981 (MCMLXXXI) was a common year starting on Thursday (link displays the 1981 Gregorian calendar). ... The 64 meter radio telescope at Parkes Observatory A radio telescope is a form of directional radio antenna most often used in radio astronomy and in tracking and collecting data from satellites and space probes (see Deep Space Network), and are also used in the SETI project. ... Official website: http://harvard. ...


Even 131,000 channels weren't enough to search the sky in detail at a fast rate, so Suitcase SETI was followed in 1985 by Project "META", for "Megachannel Extra-Terrestrial Assay". The META spectrum analyzer had a capacity of 8.4 million channels and a channel resolution of 0.05 hertz. An important feature of META was its use of frequency doppler shift to distinguish between signals of terrestrial and extraterrestrial origin. The project was led by Horowitz with the help of the Planetary Society, and was partly funded by movie maker Steven Spielberg. A second such effort, META II, was begun in Argentina in 1990 to search the southern sky. META II is still in operation, after an equipment upgrade in 1996. Year 1985 (MCMLXXXV) was a common year starting on Tuesday (link displays 1985 Gregorian calendar). ... The Doppler effect is the apparent change in frequency or wavelength of a wave that is perceived by an observer moving relative to the source of the waves. ... Year 1990 (MCMXC) was a common year starting on Monday (link displays the 1990 Gregorian calendar). ... Year 1996 (MCMXCVI) was a leap year starting on Monday (link will display full 1996 Gregorian calendar). ...


The follow-on to META was named "BETA", for "Billion-channel ExtraTerrestrial Assay", and it commenced observation on October 30, 1995. The heart of BETA's processing capability consisted of 63 dedicated FFT engines, each capable of performing a 2^22-point complex fast Fourier transform in two seconds, and 21 general-purpose PCs equipped with custom digital signal processing boards. This allowed BETA to receive 250 million simultaneous channels with a resolution of 0.5 hertz per channel. It scanned through the microwave spectrum from 1.400 to 1.720 gigahertz in eight hops, with two seconds of observation per hop. An important capability of the BETA search was rapid and automatic re-observation of candidate signals, achieved by observing the sky with two adjacent beams, one slightly to the east and the other slightly to the west. A successful candidate signal would first transit the east beam, and then the west beam and do so with a speed consistent with the earth's sidereal rotation rate. A third receiver observed the horizon to veto signals of obvious terrestrial origin. On March 23, 1999 the 26-meter radio telescope on which Sentinel, META and BETA were based was blown over by strong winds and seriously damaged. This forced the BETA project to cease operation. October 30 is the 303rd day of the year (304th in leap years) in the Gregorian calendar, with 62 days remaining. ... Year 1995 (MCMXCV) was a common year starting on Sunday (link will display full 1995 Gregorian calendar). ... The Fast Fourier Transform (FFT) is an efficient algorithm to compute the discrete Fourier transform (DFT) and its inverse. ... In mathematics, a complex number is a number of the form where a and b are real numbers, and i is the imaginary unit, with the property i 2 = −1. ... The Fast Fourier Transform (FFT) is an efficient algorithm to compute the discrete Fourier transform (DFT) and its inverse. ... This article or section does not cite its references or sources. ... Digital signal processing (DSP) is the study of signals in a digital representation and the processing methods of these signals. ... Microwaves are electromagnetic waves with wavelengths longer than those of terahertz (THz) frequencies, but relatively short for radio waves. ... In most modern usages of the word spectrum, there is a unifying theme of between extremes at either end. ... The orbital period is the time it takes a planet (or another object) to make one full orbit. ... is the 82nd day of the year (83rd in leap years) in the Gregorian calendar. ... Year 1999 (MCMXCIX) was a common year starting on Friday (link will display full 1999 Gregorian calendar). ... The 64 meter radio telescope at Parkes Observatory A radio telescope is a form of directional radio antenna most often used in radio astronomy and in tracking and collecting data from satellites and space probes (see Deep Space Network), and are also used in the SETI project. ...


MOP and Project Phoenix

In 1992, the U.S. government funded an operational SETI program, in the form of the NASA "Microwave Observing Program (MOP)". MOP was planned as a long-term effort, performing a "Targeted Search" of 800 specific nearby stars, along with a general "Sky Survey" to scan the sky. MOP was to be performed by radio dishes associated with the NASA Deep Space Network, as well as a 43-meter dish at Green Bank and the big Arecibo dish. The signals were to be analyzed by spectrum analyzers, each with a capacity of 15 million channels. These spectrum analyzers could be ganged to obtain greater capacity. Those used in the Targeted Search had a bandwidth of 1 hertz per channel, while those used in the Sky Survey had a bandwidth of 30 hertz per channel. Year 1992 (MCMXCII) was a leap year starting on Wednesday (link will display full 1992 Gregorian calendar). ... Deep Space Network (DSN) is an international network of radio antennas that supports interplanetary spacecraft missions, and radio and radar astronomy observations for the exploration of the solar system and the universe. ...


MOP drew the attention of the U.S. Congress, where the program was strongly ridiculed, and was canceled a year after its start. SETI advocates did not give up, and in 1995 the nonprofit SETI Institute of Mountain View, California, resurrected the work under the name of Project "Phoenix", backed by private sources of funding. Project Phoenix, under the direction of Dr. Jill Tarter, previously Project Scientist for the NASA project, is a continuation of the Targeted Search program, studying roughly 1,000 nearby Sun-like stars. Seth Shostak also worked on Project Phoenix. From 1995 through March 2004, Phoenix conducted observing campaigns at the 64-meter Parkes radio telescope in Australia, the 140 Foot Telescope of the National Radio Astronomy Observatory in West Virginia, USA, and the Arecibo Observatory in Puerto Rico. The project observed the equivalent of 800 stars over the available channels in the frequency range from 1200 to 3000 MHz. The search was sensitive enough to pick up transmitters with power output equivalent to airport radars to a distance of about 200 light years. The Congress of the United States is the legislative branch of the federal government of the United States of America. ... Year 1995 (MCMXCV) was a common year starting on Sunday (link will display full 1995 Gregorian calendar). ... The SETI Institute is a private, nonprofit organization dedicated to scientific research, education and public outreach to explore, understand, and explain the nature and origin of the Universe. ... For the community near Martinez, California, see Mountain View, Contra Costa County, California. ... Project Phoenix is a SETI project: a search for extraterrestrial intelligence by listening for radio signals. ... Jill Cornell Tarter (born 1944) is an American astronomer and the current director of the Center for SETI Research. ... Seth Shostak. ... The big dish The Parkes Observatory is a radio telescope observatory, 20 kilometres north of the town of Parkes, New South Wales, Australia. ...


Allen Telescope Array

Main article: Allen Telescope Array

The SETI Institute is now collaborating with the Radio Astronomy Laboratory at UC Berkeley to develop a specialized radio telescope array for SETI studies, something like a mini-Cyclops array. The new array concept is named the "Allen Telescope Array" (ATA) (formerly, One Hectare Telescope [1HT]) after the project's benefactor Paul Allen. Its sensitivity will be equivalent to a single large dish more than 100 meters in diameter. The array is being constructed at the Hat Creek Observatory in rural northern California. [7] ATA Dish Size Scale The Allen Telescope Array (ATA), formerly known as the One Hectare Telescope (1hT), is a joint effort by the SETI Institute and the Radio Astronomy Laboratory at the University of California, Berkeley to construct a radio interferometer that will be dedicated to astronomical and simultaneous search... Paul Gardner Allen (born January 21, 1953 in Seattle, Washington) is an American entrepreneur who formed Microsoft with Bill Gates. ... The Hat Creek Radio Observatory (HCRO) is a radio telescope near the town of Hat Creek in Shasta County, California. ...


The full array is planned to consist of 350 or more Gregorian radio dishes, each 6.1 meters (20 feet) in diameter. These dishes are the largest producible with commercially available satellite television dish technology. The ATA was planned for a 2007 completion date, at a very modest cost of $25 million USD. The SETI Institute provides money for building the ATA while UC Berkeley designs the telescope and provides operational funding. Berkeley astronomers will use the ATA to pursue other deep space radio observations. The ATA is intended to support a large number of simultaneous observations through a technique known as "multibeaming", in which DSP technology is used to sort out signals from the multiple dishes. The DSP system planned for the ATA is extremely ambitious. Artists impression of a Boeing 601 satellite, as configured for digital television transmission by SES Astra Satellite television is television delivered by way of communications satellites, as compared to conventional terrestrial television and cable television. ...


As of summer 2006, roughly 10 of the antennas are complete and 42 are under final construction. Although not yet capable of significant radio astronomy or SETI observations, the ATA has become a testbed for array technology, as needed for the Square Kilometre Array, the US Navy, and DARPA. Completion of the full 350 element array will depend on funding and the technical results from the 42 element sub-array. The Square Kilometre Array, once complete will be a radio telescope with a planned collecting area of a square kilometre. ...


Optical SETI experiments

While most SETI sky searches have studied the radio spectrum, some SETI researchers have considered the possibility that alien civilizations might be using powerful lasers for interstellar communications at optical wavelengths. The idea was first suggested in a paper published in the British journal Nature in 1961, and in 1983 Charles Townes, one of the inventors of the laser, published a detailed study of the idea in the US journal Proceedings of the National Academy of Sciences. Most SETI researchers agreed with the idea. The 1971 Cyclops study discounted the possibility of optical SETI, reasoning that construction of a laser system that could outshine the bright central sun of a remote star system would be too difficult. Now some SETI advocates, such as Frank Drake, have suggested that such a judgment was too conservative. Experiment with a laser (US Military) In physics, a laser is a device that emits light through a specific mechanism for which the term laser is an acronym: Light Amplification by Stimulated Emission of Radiation. ... Nature is one of the most prominent scientific journals, first published on 4 November 1869. ... Charles Hard Townes (born July 28, 1915) is an American Nobel Prize-winning physicist and educator. ... The Proceedings of the National Academy of Sciences of the United States of America, usually referred to as PNAS, is the official journal of the United States National Academy of Sciences. ... Professor Frank Drake Frank Drake (born May 28, 1930, Chicago, Illinois) is an American astronomer and astrophysicist. ...


There are two problems with optical SETI. The first problem is that lasers are highly "monochromatic", that is, they emit light only on one frequency, making it troublesome to figure out what frequency to look for. However, according to Harmonic analysis (Fourier analysis), emitting light in narrow pulses results in a broad spectrum of emission (due to the uncertainty principle), with the frequencies becoming higher as the pulse width becomes narrower, and an interstellar communications system could use pulsed lasers. Harmonic analysis is the branch of mathematics which studies the representation of functions or signals as the superposition of basic waves. ... In quantum physics, the Heisenberg uncertainty principle is a mathematical property of a pair of canonical conjugate quantities - usually stated in a form of reciprocity of spans of their spectra. ...


The other problem is that while radio transmissions can be broadcast in all directions, lasers are highly directional. This means that a laser beam could be easily blocked by clouds of interstellar dust, and Earth would have to cross its direct line of fire by chance to receive it. Interstellar cloud is the generic name given to accumulations of gas and dust in our galaxy. ...


Optical SETI supporters have conducted paper studies of the effectiveness of using contemporary high-energy lasers and a ten-meter focus mirror as an interstellar beacon. The analysis shows that an infrared pulse from a laser, focused into a narrow beam by a such a mirror, would appear thousands of times brighter than the Sun to a distant civilization in the beam's line of fire. The Cyclops study proved incorrect in suggesting a laser beam would be inherently hard to see.


Such a system could be made to automatically steer itself through a target list, sending a pulse to each target at a constant rate. This would allow targeting of all Sun-like stars within a distance of 100 light-years. The studies have also described an automatic laser pulse detector system with a low-cost, two-meter mirror made of carbon composite materials, focusing on an array of light detectors. This automatic detector system could perform sky surveys to detect laser flashes from civilizations attempting contact.


In the 1980s, two Soviet researchers conducted a short optical SETI search, but turned up nothing. During much of the 1990s, the optical SETI cause was kept alive through searches by Stuart Kingsley, a dedicated British amateur living in the US state of Ohio. Dr. Stuart A. Kingsley maintains a Web page which details his work with Optical SETI (OSETI) and contains a great deal of information and links on OSETI and SETI in general. ...


Several optical SETI experiments are now in progress. A Harvard-Smithsonian group that includes Paul Horowitz designed a laser detector and mounted it on Harvard's 155 centimeter (61 inch) optical telescope. This telescope is currently being used for a more conventional star survey, and the optical SETI survey is "piggybacking" on that effort. Between October 1998 and November 1999, the survey inspected about 2,500 stars. Nothing that resembled an intentional laser signal was detected, but efforts continue. The Harvard-Smithsonian group is now working with Princeton to mount a similar detector system on Princeton's 91-centimeter (36-inch) telescope. The Harvard and Princeton telescopes will be "ganged" to track the same targets at the same time, with the intent being to detect the same signal in both locations as a means of reducing errors from detector noise. A multiple piggyback. ...


The Harvard-Smithsonian group is now building a dedicated all-sky optical survey system along the lines of that described above, featuring a 1.8-meter (72-inch) telescope. The new optical SETI survey telescope is being set up at the Oak Ridge Observatory in Harvard, Massachusetts. The Oak Ridge Observatory is operated by the Harvard-Smithsonian Center for Astrophysics as a facility of the Smithsonian Astrophysical Observatory (SAO), and houses the largest telescope east of Texas in the United States, a 61-inch reflector. ... Official website: http://harvard. ...


The University of California, Berkeley, home of SERENDIP and [email protected], is also conducting optical SETI searches. One is being directed by Geoffrey Marcy, an extrasolar planet hunter, and involves examination of records of spectra taken during extrasolar planet hunts for a continuous, rather than pulsed, laser signal. The other Berkeley optical SETI effort is more like that being pursued by the Harvard-Smithsonian group and is being directed by Dan Werthimer of Berkeley, who built the laser detector for the Harvard-Smithsonian group. The Berkeley survey uses a 76-centimeter (30-inch) automated telescope and an older laser detector built by Werthimer. Image:Geoff marcy. ... An extrasolar planet, or exoplanet, is a planet beyond the Solar System. ...


Probe SETI and SETA experiments

The possibility of using interstellar messenger probes in the search for extraterrestrial intelligence was first suggested by Ronald N. Bracewell in 1960 (see Bracewell probe), and the technical feasibility of this approach was demonstrated by the British Interplanetary Society's starship study Project Daedalus in 1978. Starting in 1979, Robert Freitas advanced arguments [8] [9] [10] for the proposition that physical space-probes are a superior mode of interstellar communication to radio signals. Ronald Newbold Bracewell (1921 – ) is the Lewis M. Terman Professor of Electrical Engineering, Emeritus of the Space, Telecommunications and Radioscience Laboratory at Stanford University. ... A Bracewell probe is a hypothetical concept for an autonomous interstellar probe dispatched for the express purpose for communication with (an) alien civilization(s). ... An artists conception of the British Interplanetary Society design for Project Daedalus Project Daedalus was a study conducted between 1973 and 1978 by the British Interplanetary Society to design a plausible interstellar unmanned spacecraft. ... Robert A. Freitas Jr. ...


Subsequently, in a September 2004 paper featured on the cover of Nature [11], Christopher Rose and Gregory Wright showed that inscribing a message in matter and transporting it to the destination is vastly more energy efficient than communication using electromagnetic waves if the message can tolerate delivery delay beyond light transit time [12] [13] [14]. Thus, a solarcentric Search for Extraterrestrial Artifacts (SETA) [15] would seem to be favored over the more traditional radio or optical searches. Nature is one of the most prominent scientific journals, first published on 4 November 1869. ... Christopher Rose is a professor of electrical and computer engineering at Rutgers University in New Jersey. ... Gregory A. Wright is an astrophysicist and independent consultant with Antiope Associates. ...


Much like the "preferred frequency" concept in SETI radio beacon theory, the Earth-Moon or Sun-Earth libration orbits [16] might therefore constitute the most universally convenient parking places for automated extraterrestrial spacecraft exploring arbitrary stellar systems. A viable long-term SETI program may be founded upon a search for these objects. The animation shows a set of simulated views of the Moon over one month. ...


In 1979 Freitas and Valdes[16] A Search for Natural or Artificial Objects Located at the Earth-Moon Libration Pointsconducted a photographic search of the vicinity of the Earth-Moon triangular libration points L4 and L5, and of the solar-synchronized positions in the associated halo orbits, seeking possible orbiting extraterrestrial interstellar probes, but found nothing to a detection limit of about 14th magnitude. The authors conducted a second, more comprehensive photographic search for probes in 1982 [17] that examined the five Earth-Moon Lagrangian positions and included the solar-synchronized positions in the stable L4/L5 libration orbits, the potentially stable nonplanar orbits near L1/L2, Earth-Moon L3, and also L2 in the Sun-Earth system. Again no extraterrestrial probes were found to limiting magnitudes of 17-19th magnitude near L3/L4/L5, 10-18th magnitude for L1/L2, and 14-16th magnitude for Sun-Earth L2. A Lagrangian of a dynamical system, named after Joseph Louis Lagrange, is a function of the dynamical variables and concisely describes the equations of motion of the system. ...


In June 1983, Valdes and Freitas [18] used the 26-m radiotelescope at Hat Creek Radio Observatory to search for the tritium hyperfine line at 1516 MHz from 108 assorted astronomical objects, with emphasis on 53 nearby stars including all visible stars within a 20 light-year radius. The tritium frequency was deemed highly attractive for SETI work because (1) the isotope is cosmically rare, (2) the tritium hyperfine line is centered in the SETI waterhole region of the terrestrial microwave window, and (3) in addition to beacon signals, tritium hyperfine emission may occur as a byproduct of extensive nuclear fusion energy production by extraterrestrial civilizations. The wideband- and narrowband-channel observations achieved sensitivities of 5-14 x 10-21 W/m2/channel and 0.7-2 x 10-24 W/m2/channel, respectively, but no detections were made.


Where are they?

Main article: Fermi paradox

Italian physicist Enrico Fermi suggested in the 1950s that if technologically advanced civilizations are common in the universe, then they should be detectable in one way or another. (According to those who were there[19], Fermi either asked "Where are they?" or "Where is everybody?") A graphical representation of the Arecibo message - Humanitys first attempt to use radio waves to communicate its existence to alien civilizations The Fermi paradox is the apparent contradiction between high estimates of the probability of the existence of extraterrestrial civilizations and the lack of evidence for or contact with... Enrico Fermi (September 29, 1901 – November 28, 1954) was an Italian physicist most noted for his work on the development of the first nuclear reactor, and for his contributions to the development of quantum theory, particle physics and statistical mechanics. ...


The Fermi paradox can be stated more completely as follows:

The size and age of the universe incline us to believe that many technologically advanced civilizations must exist. However, this belief seems logically inconsistent with our lack of observational evidence to support it. Either the initial assumption is incorrect and technologically advanced intelligent life is much rarer than we believe, our current observations are incomplete and we simply have not detected them yet, or our search methodologies are flawed and we are not searching for the correct indicators.

Possible explanations for the paradox suggest, for example, that while simple life may well be abundant in the universe, intelligent life may be exceedingly rare. In 2000, Peter Ward, professor of Biology and of Earth and Space Sciences at the University of Washington authored a book claiming the Rare Earth hypothesis. In short, the theory claims that the emergence of complex multicellular life (metazoa) on Earth required an extremely unlikely combination of astrophysical and geological events and circumstances. This hypothesis contradicts the principle of mediocrity, which SETI takes as an assumption. 2000 (MM) was a leap year starting on Saturday of the Gregorian calendar. ... Peter D. Ward is a paleontologist and professor of Biology and of Earth and Space Sciences at the University of Washington. ... The University of Washington, founded in 1861, is a public research university in Seattle, Washington. ... The Rare Earth hypothesis is a hypothesis in planetary astronomy and astrobiology which argues that the emergence of complex multicellular life (metazoa) on Earth required an extremely unlikely combination of astrophysical and geological events and circumstances. ... Multicellular organisms are those organisms consisting of more than one cell, and having differentiated cells that perform specialized functions. ... Phyla Radiata Cnidaria Ctenophora - Comb jellies Bilateria Protostomia Acoelomorpha Platyhelminthes - Flatworms Nemertina - Ribbon worms Gastrotricha Gnathostomulida - Jawed worms Micrognathozoa Rotifera - Rotifers Acanthocephala Priapulida Kinorhyncha Loricifera Entoprocta Nematoda - Roundworms Nematomorpha - Horsehair worms Cycliophora Mollusca - Mollusks Sipuncula - Peanut worms Annelida - Segmented worms Tardigrada - Water bears Onychophora - Velvet worms Arthropoda - Insects, etc. ... Spiral Galaxy ESO 269-57 Astrophysics is the branch of astronomy that deals with the physics of the universe, including the physical properties (luminosity, density, temperature and chemical composition) of astronomical objects such as stars, galaxies, and the interstellar medium, as well as their interactions. ... Geology (from Greek γη- (ge-, the earth) and λογος (logos, word, reason)) is the science and study of the Earth, its composition, structure, physical properties, history, and the processes that shape it. ... The mediocrity principle is the notion in the philosophy of science that there is nothing special about Earth, and by implication the human race. ...


Another suggestion, made by astrophysicist Ray Norris in 1999 in Acta Astronautica (and subsequently in Allen Tough's book When SETI Succeeds: The Impact of High-Information Contact - ISBN 0-9677252-2-4) was that gamma-ray burst events are sufficiently frequent to sterilize vast swaths of galactic real-estate. This idea was subsequently popularized by physicist Arnon Dar, and described in the PBS Nova show 'Death Star'. Year 1999 (MCMXCIX) was a common year starting on Friday (link will display full 1999 Gregorian calendar). ... In astronomy, gamma-ray bursts (GRBs) are flashes of gamma rays that last from seconds to hours, the longer ones being followed by several days of X-ray afterglow. ...


Science writer Timothy Ferris has suggested that since galactic societies could be only transitory, then if there is in fact an interstellar communications network, it consists mostly of automated systems that store the cumulative knowledge of vanished civilizations and communicate that knowledge through the galaxy. Ferris calls this the "Interstellar Internet", with the various automated systems acting as network "servers". Ferris suspects that if such an Interstellar Internet exists, communications between servers are mostly through narrow-band, highly directional radio or laser links. Intercepting such signals is, as discussed earlier, very difficult. However, the network could maintain some broadcast nodes in hopes of making contact with new civilizations. Timothy Ferris (born August 29, 1944) is the best-selling author of twelve books, including Coming of Age in the Milky Way, for which he was awarded the American Institute of Physics Prize, and a nomination for the Pulitzer Prize. ...


Others believe that intelligent life will communicate through obvious medium directed to the masses. Such a communication would be subtle and gradiated. The internet now provides such a medium that can be used by life outside earth to communicate.


Public information

In 2005, the International Academy of Astronautics established the SETI: Post-Detection Science and Technology Taskgroup (Chairman, Professor Paul Davies) "to act as a Standing Committee to be available to be called on at any time to advise and consult on questions stemming from the discovery of a putative signal of extraterrestrial intelligent (ETI) origin." [1] It will use, in part, the Rio Scale [2] to evaluate the importance of releasing the information to the public. The International Academy of Astronautics (IAA) is an international community of experts committed to expanding the frontiers of space. ... Paul Charles William Davies (born April 22, 1946) is a British-born, internationally acclaimed physicist, writer and broadcaster, who holds the position of College Professor at Arizona State University. ... The Rio Scale is a proposed scale for assessing the importance of a signal received on Earth from possible extra-terrestrial intelligent civilizations. ...


Criticism of SETI

Is SETI worth the cost?

As various SETI projects have continued, some have criticized early claims by researchers now seen to be too "euphoric" or "optimistic." For example, Peter Schenkel, while remaining a supporter of SETI projects, has written that "[i]n light of new findings and insights, it seems appropriate to put excessive euphoria to rest and to take a more down-to-earth view ... We should quietly admit that the early estimates - that there may be a million, a hundred thousand, or ten thousand advanced extraterrestrial civilizations in our galaxy - may no longer be tenable." [3].


SETI has also occasionally been the target of criticism by those who suggest that it is a form of pseudoscience. In particular, critics allege that no observed phenomena suggest the existence of extraterrestrial intelligence, and furthermore that the assertion of the existence of extraterrestrial intelligence has no good Popperian criteria for falsifiability [4]. Science fiction writer Michael Crichton, in a 2003 lecture at Caltech, stated that "The Drake equation cannot be tested and therefore SETI is not science. SETI is unquestionably a religion." [5]. Phrenology is regarded today as a classic example of pseudoscience. ... Sir Karl Raimund Popper, CH, FRS, FBA, (July 28, 1902 – September 17, 1994), was an Austrian born naturalized British[1] philosopher and a professor at the London School of Economics. ... In science and the philosophy of science, falsifiability is the logical property of empirical statements, related to contingency and defeasibility, that they must admit of logical counterexamples. ... Science fiction is a form of speculative fiction principally dealing with the impact of imagined science and technology, or both, upon society and persons as individuals. ... Michael Crichton (born October 23, 1942, pronounced [1]) is an American author, film producer, film director, and television producer. ... California Institute of Technology The California Institute of Technology (commonly known as Caltech) is a private, coeducational university located in Pasadena, California, in the United States. ... The Drake equation (also known as the Green Bank equation or the Sagan equation) is a famous result in the speculative fields of xenobiology, astrosociobiology and the search for extraterrestrial intelligence. ...


In response, SETI advocates note, among other things, that the existence of intelligent life on Earth is a plausible reason to expect it elsewhere, and that individual SETI projects have clearly defined "stop" conditions. Concerning the latter argument, the justification for SETI projects doesn't necessarily require an acceptance of the Drake equation. In addition it should be noted that the Drake equation by itself is not an hypothesis and hence it is not even supposed to be testable. The equation can serve as a tool in formulating testable hypotheses.


The search for extra-terrestrial intelligence is not an assertion that extra-terrestrial intelligence exists, and conflating the two can be seen as a straw man argument. There is an effort to distinguish the SETI projects from UFOlogy, the study of UFOs considered to be pseudoscience by many. In Skeptical Inquirer, Mark Moldwin explicitly made the distinction between the two projects, arguing that an important discriminator was the acceptance of SETI by the mainstream scientific community and that "[t]he methodology of SETI leads to useful scientific results even in the absence of discovery of alien life." [6] A straw man or man of straw is a dummy in the shape of a human created by stuffing straw into clothes. ... Ufology is the study of unidentified flying object (UFO) reports, sightings, alleged physical evidence, and other related phenomena. ... The Skeptical Inquirer is a magazine of the Committee for the Scientific Investigation of Claims of the Paranormal (CSICOP) dedicated to debunking pseudoscience. ...


Is "active" SETI dangerous?

Positive SETI (also known as "active SETI" or as METI = "messages to extraterrestrial intelligence") consists of directing signals into space in the hope that they will be picked up by an alien intelligence. Some feel that this activity contains improbable but real dangers and ought to be discussed more broadly before it is undertaken. However, that concern is rendered moot by an examination of recent history. Television and radio signals have been broadcast into space for decades, and coherent signals are easily differentiated from random noise.


The concern over SETI was raised by the science journal Nature in an editorial in October 2006, which commented on a recent meeting of the International Academy of Astronautics SETI study group. The editor said, “It is not obvious that all extraterrestrial civilizations will be benign, or that contact with even a benign one would not have serious repercussions”. (Nature Vol 443 12 Oct 06 p 606). Astronomer and science fiction author David Brin has expressed similar concerns. The International Academy of Astronautics (IAA) is an international community of experts committed to expanding the frontiers of space. ... Glen David Brin, Ph. ...


Is SETI a product of culture or science?

Carl Sagan once expressed his surprise when people asked him whether he believed in SETI as if it were a matter of faith. The idea that SETI may be driven for a search for an authority figure is investigated by science historian George Basala in Civilized Life in the Universe, and by astrophysicist J.M. Perelmuter in the science novel The Sinusoidal Spaghetti which juxtaposes an astronomer with Tourette syndrome who claims to have found a message in the signal of a pulsar, and his psychiatrist who thinks it is a product of his mind and the collective subconscious. Insert non-formatted text here Carl Edward Sagan (November 9, 1934 – December 20, 1996) was an American astronomer and astrobiologist and a highly successful popularizer of astronomy, astrophysics, and other natural sciences. ... Faith has two general implications which can be implied either exclusively or mutually; To Trust: Believing a certain variable will act a specific way despite the potential influence of known or unknown change. ... Tourette syndrome (also called Tourettes syndrome, Tourettes disorder, Gilles de la Tourette syndrome, GTS or, more commonly, simply Tourettes or TS) is an inherited neurological disorder with onset in childhood, characterized by the presence of multiple physical (motor) tics and at least one vocal (phonic) tic; these...


See also

[email protected] logo [email protected] (SETI at home) is a distributed computing project using Internet-connected computers, hosted by the Space Sciences Laboratory, at the University of California, Berkeley, in the United States. ... CETI (Communication with Extraterrestrial Intelligence, or METI, Messaging to Extraterrestrial Intelligence) is a branch of SETI research that focuses on composing and deciphering messages that could theoretically be understood by another technological civilization. ... “Green people” redirects here. ... Pigments other than green might dominate plant life on exoplanets[1] The DNA structure might not be the only nucleic acid in the universe capable of supporting life[2] Astrobiology (from Greek: ἀστρο, astro, constellation; βίος, bios, life; and λόγος, logos, knowledge) is the study of life in space, combining aspects of astronomy... The Drake equation (also known as the Green Bank equation or the Sagan equation) is a famous result in the speculative fields of xenobiology, astrosociobiology and the search for extraterrestrial intelligence. ... A graphical representation of the Arecibo message - Humanitys first attempt to use radio waves to communicate its existence to alien civilizations The Fermi paradox is the apparent contradiction between high estimates of the probability of the existence of extraterrestrial civilizations and the lack of evidence for or contact with... First contact is a term used to describe a first meeting of two previously unknown cultures. ... The WOW! Signal Credit: The Ohio State University Radio Observatory and the North American AstroPhysical Observatory (NAAPO). ... Darwin is a proposed European Space Agency (ESA) mission designed to directly detect Earth-like planets orbiting nearby stars, and search for evidence of life on these planets. ... Terrestrial Planet Finder - Infrared interferometer concept The Terrestrial Planet Finder (TPF) is a plan by NASA for a telescope system that would be capable of detecting extrasolar terrestrial planets. ... The Big Ear was a radio telescope located on the grounds of the Ohio Wesleyan Universitys The Perkins Observatory from the 1960s to 1998 when it was disassembled. ... Contact is a science fiction novel written by Carl Sagan and published in 1985. ... This article or section contains a plot summary that is overly long. ...

References and notes

  1. ^ If SETI is Science and UFOlogy Is Not, Which Is Intelligent Design Theory? - By Peter S. Williams (MA, MPhil)
  2. ^ Sagan, Carl; Iosif Shklovskii (1966). Intelligent Life in the Universe. 
  3. ^ SERENDIP. UC Berkeley. Retrieved on 2006-06-12.
  4. ^ [email protected] Classic - Current Total Statistics. Retrieved on 2006-06-12.
  5. ^ BOINCstats. Retrieved on 2006-06-12.
  6. ^ BOINC Stats
  7. ^ Allen Telescope Array General Overview. SETI Institute. Retrieved on 2006-06-12.
  8. ^ Interstellar probes - A new approach to SETI - by Robert A. Freitas Jr.
  9. ^ Debunking the Myths of Interstellar Probes - by Robert A. Freitas Jr.
  10. ^ The Case for Interstellar Probes - by Robert A. Freitas Jr.
  11. ^ Nature Magazine - Volume 431 Number 7004 pp1-109, issue (2 September 2004)
  12. ^ Nature Magazine - with registration
  13. ^ Inscribed matter as an energy efficient means of communication with an extraterrestrial civilization - winlab.rutgers.edu
  14. ^ Cosmic Communications - winlab.rutgers.edu
  15. ^ The Search for Extraterrestrial Artifacts (SETA) - by Robert A. Freitas Jr., Xenology Research Institute
  16. ^ a b
  17. ^ A Search for Objects near the Earth-Moon Lagrangian Points - By Francisco Valdes
  18. ^ A Search for the Tritium Hyperfine Line from Nearby Stars - By Francisco Valdes
  19. ^ Eric Jones, "Where is everybody?", An account of Fermi's question", Los Alamos Technical report LA-10311-MS, March, 1985.

The University of California, Berkeley (also known as Cal, UC Berkeley, UCB, or simply Berkeley) is a prestigious, public, coeducational university situated in the foothills of Berkeley, California to the east of San Francisco Bay, overlooking the Golden Gate and its bridge. ... For the Manfred Mann album, see 2006 (album). ... is the 163rd day of the year (164th in leap years) in the Gregorian calendar. ... For the Manfred Mann album, see 2006 (album). ... is the 163rd day of the year (164th in leap years) in the Gregorian calendar. ... For the Manfred Mann album, see 2006 (album). ... is the 163rd day of the year (164th in leap years) in the Gregorian calendar. ... The SETI Institute is a private, nonprofit organization dedicated to scientific research, education and public outreach to explore, understand, and explain the nature and origin of the Universe. ... For the Manfred Mann album, see 2006 (album). ... is the 163rd day of the year (164th in leap years) in the Gregorian calendar. ...

Further reading

  • Exers, Ronald, D. Cullers, J. Billingham, L. Scheffer (editors) (2003). SETI 2020: A Roadmap for the Search for Extraterrestrial Intelligence. SETI Press. ISBN 0-9666335-3-9. 
  • McConnell, Brian; Chuck Toporek (2001). Beyond Contact: A Guide to SETI and Communicating with Alien Civilizations. O'Reilly. ISBN 0-596-00037-5. 
  • Perelmuter, J.M. (2006). The Sinusoidal Spaghetti. iUniverse. ISBN 0-595-41713-2. 

External links

Organizations
Academic journals, reports and publications
News
Articles and FAQ's
Videos

  Results from FactBites:
 
Egypt: Seti (Sethos) I (827 words)
Seti I was the father of perhaps Egypt's greatest rulers, Ramesses II, and was in his own right also a great leader.
Seti's reliefs are on the north side and their fine style is evident when compared to later additions.
Seti's mummy is said to be the finest of all surviving royal mummies, though it was not found in his tomb.
  More results at FactBites »

 
 

COMMENTARY     


Share your thoughts, questions and commentary here
Your name
Your comments

Want to know more?
Search encyclopedia, statistics and forums:

 


Press Releases |  Feeds | Contact
The Wikipedia article included on this page is licensed under the GFDL.
Images may be subject to relevant owners' copyright.
All other elements are (c) copyright NationMaster.com 2003-5. All Rights Reserved.
Usage implies agreement with terms, 1022, m