THE SEARCH FOR EXTRATERRESTRIAL INTELLIGENCE

Posted by admin_akashic on Jun 27th, 2022 in Space

Such examples of anthropocentrism are as amusing as they are obvious. But are the SETI scientists and the bioastronomical community immune from it and equally as selective in their approach?

Attempts to communicate with ETI during the 1970s involved the Pioneer and Voyager spacecrafts. Pioneers 10 and 11 were launched in 1972 towards Jupiter and Saturn on trajectories that would eventually take them beyond the solar system. They carried plaques depicting men and women. The background story of these plaques reveals much about terrestrial politics of the late twentieth century. The drawing of the man and woman depicted them without any clothes. While no genitalia were included in the drawing, NASA was strongly condemned in the US media for sending pornography into space. The faces of the human figures had to be modified to be more ethnically diverse, and women’s representatives questioned why only the man’s hand was raised in a peaceful greeting. In the summer of 1977 Voyagers I and II were launched by NASA from Cape Canaveral on an exploratory mission to return data from Jupiter, Saturn, Uranus and Neptune, then leaving the solar system for an endless journey through space. These spacecraft carry a 12-inch copper disc entitled Sounds of the Earth, which carries a message from Kurt Waldheim, former Secretary General of the United Nations, and a message from the US President, James Carter, saying that the USA is a ‘community of 240 million human beings among the more than 4 billion who inhabit the Earth’. The disc also contains a selection of sounds of footsteps, heartbeats, laughter and a sample of music from Stravinsky, Louis Armstrong and Chuck Berry. The technology which would be used to play the message is already obsolete on Earth. Were Voyager to return in a couple of centuries it would be extremely difficult to extract its message. Other information aboard the craft includes an essay on the evolution of the Earth, our location in the galaxy, pictures of a forest scene, snowflakes, a supermarket, an elephant, peasant workers, the Great Wall of China, the Sydney Opera House and various street scenes. Both of the Voyager spacecraft have now left the solar system, travelling at a rate of 300 million miles a year. It will take them about 40,000 more years before they reach another star. So far there has been no response from any potential recipient.

Another proposal for an interplanetary message has been made by NASA and European Space Agency’s spaceflight, Cassini, launched at Saturn’s moon, Titan, on 15 October 1997 after a two-day delay due to computer malfunction. This message, which was jointly proposed by the radio astronomer, Gregory Benford and space artist, Jon Lomberg, will be aboard the Titan lander, called Huygens, and was made of diamond which can survive for a billion years to be read if intelligent life evolves out of Titan’s primeval soup, or by other interplanetary travellers. In the event, 600,000 signatures were collected and recorded on a CD. One optimistic hope is that it will be read by our descendants when they explore the outer parts of the solar system, but it is more likely that the meaning of such messages is bound up with a desire to ignite public interest in the space programme.

It is, of course, extremely unlikely that the messages aboard the Pioneer, Voyager and the Cassini spacecrafts would initiate a two-way dialogue. This was not the intention. Moreover, if any of these messages is discovered and translated by intelligent extraterrestrials in about 40,000 years’ time it will hardly be representative of life on Earth as it will exist then. The great mass of the universe is a past universe. We can only observe it as it was. The actual universe is unobservable. Contact with extraterrestrials is unlikely to involve any sustainable dialogue. But one-way contact from the past would still have tremendous significance. Our lives today are very much shaped by messages and statements from the past, including the Judaeo-Christian Bible and other ancient texts.

Developments this century have expanded the scope of the observable universe. Whereas earlier thinkers pondered over the theoretical possibility of extraterrestrial life, SETI investigators now have the facilities to conduct an empirical search. Already SETI research is underway for the detection of micro-organisms in the solar system, with particular emphasis on Mars. By definition SETI is an experimental science. SETI researchers insist that claims about the existence of ETI cannot be substantiated by appeal to theory, no matter how compelling the arguments. Observational developments in twentieth-century astronomy have been enhanced by techniques involving radio astronomy and X-ray astronomy. Prospects of an ETI encounter have been primarily linked with developments in radio communication.

Radio communication

Radio astronomy

Radio astronomy began in 1931 when the US communications engineer, Karl Jansky, constructed a large aerial to track down the source of disturbances to long-range radio transmissions. He discovered radio signals emanating from the centre of the galaxy. The Second World War saw the development of radar, and then the building of the giant radio telescopes. After the Second World War techniques developed which led to the growth of radio astronomy, leading eventually to the discovery of previously unsuspected cosmic objects such as pulsars and quasars, leading to a transformation of our views about the universe, which turned out to be far stranger than had been imagined. The origins of SETI lie in developments in radio astronomy rather than in the space programmes of the 1960s and 1970s. This ‘new’ field of astronomy recognized that microwaves radiated from objects in space beyond those contemplated in the missions of space probes and far beyond the optical limits of conventional astronomy. In principle, intelligent signals could be transmitted from any part of the galaxy at the speed of light.