Tracking Advanced Alien Civilizations: Drake, Sentinel...

* Frank Drake, born in 1930, leading expert on methods for the detection of extraterrestrial intelligent signals. Former president of the Astronomical Society of the Pacific and currently chairman at SETI Institute. He shared in the discovery of the radiation belts of Jupiter (1959), and was among the first to show how interstellar messages could be developed for easy radio transmission. He pioneered in the development of binary coded messages from which a picture can be obtained after proper decryption of the codes, and constructed the first interstellar message ever transmitted via radio waves by our planet, i.e. Arecibo Message of November 1974. Three messages have already been sent to outer space: Pioneer 10 & 11 plaques (Sagan & Drake); the Voyager Record (Drake et al.); and the Arecibo Message (1974).

CLICK HERE TO SEE VOYAGER'S INTERSTELLAR MESSAGE

Arecibo Message (November, 1974)

* Drake also devised an equation to estimate the number of technological civilizations that might exist among the stars. There is no unique solution to this equation, but it is generally accepted by the scientific community:

N = R* fp* ne* fl* fi* fc* L

N: the number of civilizations in the Milky Way whose radio emissions are detectable.

R: the rate of formation of suitable stars with a large enough habitable zone.

fp: the fraction of those stars with planets, i.e. Sun-like stars.

ne: the number of planets per star that are capable of sustaining life.

fl: the fraction of those planets where life develops.

fi: the fraction of fl where intelligent life evolves.

fc: the fraction of fi that communicate.

L: the lifetime of communicating civilizations, i.e. ’communicating’= the idea of detectable signals into space... If we learn to protect our planet from asteroids or comets and learn to live within the limitations of our Planet, we could survive for 100's of millions of years. So L could be very large. Multiplying up the factors apart from L gives us the equation: N = L /1,000.

(c) Robotmaker, 2003

* The Sentinel Hipothesis: If advanced alien civilizations exist they might place intelligent monitoring devices on or near the worlds of other evolving species to track their progress. A robot Sentinel might establish contact with a developing race once that race had reached a certain technological threshold, such as large-scale radio communication or interplanetary flight.

* Bracewell Probes: Named after Ronald Bracewell (1960), they are automated spacecraft sent out by advanced technological races to make contact and exchange info with other intelligent beings in the galaxy. Bracewell argued that messenger probes offered an attractive alternative to the conventional SETI (http://dyg2.tripod.com/id15.html ) approach of listening for extraterrestrial signals... Bracewell probes would be powered by high-speed propulsion units, controlled by computers and sent to star systems marked as biologically interested.

* Upon arrival, the probe would enter an orbit in the middle of the star-habitable zone and in the same plane as its planetary system. This would ideally place it to make contact with any intelligent, technologically residents. The probe would then scan for radio transmissions. If there were found, it would broadcast their content back to draw attention to itself, allowing the existence and location of the probe to be established and a dialogue to be conducted... Using its onboard intelligence and memory store, the probe could pass on a vast amount of info about its origins and the civilization that had sent it, without the need to wait many years for an exchange... Among the sites regarded as most promising for scrutiny are the Earth-Moon Lagrangian points and other similar stable orbital regions in the solar system...

Lagrange Points of the Earth-Sun System

(c) Britt Griswold, 2005

* In 1974, Duncan Lunan hypothesized that a Bracewell probe was responsible for long-delay echoes first reported in the 1920s (http://dyg2.tripod.com/id5.html)... In 1995, Bracewell was among a dozen scientists selected by NASA to investigate various approaches to planet searching using interferometers in space (Space Interfderometry Mission, SIM). SIM is the first space mission to carry an optical interferometer. One of its prime goals is to search for extra solar planets as small as the Earth and in orbit around nearby stars. SIM combines the light from eight telescopes which perform sensitive astrometry so that it is able to detect very small wobbles in the movement of a star due to unseen companions. Objects of Earth mass can be inferred around a star up to 30 light-years away. SIM is also able to generate images of objects such as dust disks around stars, and look for gaps or clearings in the debris that might indicate the presence of unseen worlds...

CLICK HERE TO VISIT NASA SIM PLANET QUEST

To be continued...

CLICK HERE TO VISIT VESICA PSICIS I...

CLICK HERE TO VISIT VESICA PISCIS I

VISIT THE TEMPLE OF KARNAK

KARNAK, EGYPTIAN WISDOM, ETC.

Al-Andalus: The Land of the Vandals

Moors in Spain, Sufi Soul, Music...

THE ROOM OF INFINITE POSSIBILITIES

A NOVEL BY (C) DANIEL YANEZ 2006

(c) Daniel Yanez Gonzalez-Irun 2005

Contact me at: dannyyanezgonzalez@hotmail.co.uk