Diplomacy and the search for extraterrestrial intelligence (SETI)

Abstract Recent advances in astronomy indicate that the universe is spectacularly vast. Apparently, our Sun is like billions of other stars around which planets may circle; within just a thousand light years of Earth, for example, there are more than a million stars like the Sun. Within the Milky Way (only one of 100 billion observable galaxies) are an estimated 300–400 billion stars. Scientists now think that there are probably between 1021 and 1022 stars in the universe. With so many stars, it is highly probable that we are not alone. Just how likely extraterrestrial intelligence is or in how many places and varieties it will be found is impossible now to say. Serious scientists have constructed an equation to calculate the possibility, but the range of estimates of the number of other civilizations in the universe is so wide - anywhere from 200 million to less than 10 - and our understanding of astrophysics and cosmic evolution so primitive, that we could encounter extraterrestrials (ETs) well before it can be proved on paper that they have existed or could exist [1]. In fact, the capability to search for extraterrestrial intelligence will increase over the next five years at a rate and scale greater than at any time in human history. For example, a Harvard University observatory announced in October 1985 that it had linked a radio telescope to a new computerized multichannel spectrum analyzer and created a listening post (known as Project Meta) capable of simultaneously scanning up to 8.4 million radio channels. This development replaces a system whose capacity to search simultaneously and record radio signals was a mere 180,000 radio channels. The Hubble Space Telescope, when it is operational, will extend our present vision some seven times and possibly to the edge of the universe itself. If other planetary systems exist, this new instrument might locate them. And by the end of this decade, NASA will probably have begun a search for signals across the entire microwave spectrum while other researchers will have developed the instruments to search for large planets in orbit around some 200 nearby stars. If there is someone or thing out there trying to communicate with Earth, within the next three to five years we increasingly will know where to look and listen. This essay focuses on what to do when these or other research projects indicate that extraterrestrial intelligence exists.