First published 2009. National Geographic hardback, 2009, pp 309, c.88,000 words.
The subtitle to this book is ‘A scientist’s search for extraterrestrial intelligence’, and with that Shostak is keen to reassure us that this isn’t some wacko’s alien encounter story. The cover also tells us that Shostak is the Senior Astronomer at the SETI institute, and that there is a foreword by Frank Drake. The SETI Institute is a respectable, if somewhat quixotic, organisation that is a leader in the search for extra-terrestrial intelligence. The first professional search for alien radio signals had been made in 1960 by Frank Drake in Project Ozma. The SETI Institutes was founded in 1984 but its origins lie in a NASA arranged meeting in 1965 [p166] to discuss the possibilities of the existence of intelligent life elsewhere in the universe and humanities’ ability to detect them. As Shostak points out, the discovery of life that originated elsewhere would be truly profound. The idea of aliens out in space is a very old thought, with the first written records arising with the ancient Greeks, who indeed postulate theories very akin to currently fashionable multi-verse speculations. [p23].
At the outset, it seemed highly likely that intelligent alien life exists; after all there are several hundred billion stars in the Milky Way galaxy, and our sun is a quite average star. It seemed likely that if our sun has planets around it, suitable for the appearance of life, then many other stars surely must.
But as Drake pointed out in his famous equation, there is much more to assessing the probability that intelligent aliens are out there and wanting to communicate with us. There is the rather big question of what conditions are required to start life and have it develop to a stage where it can generate signals powerful enough that we can detect them. After all, it took four and a half billion years for life to get to that stage on this planet and if it hadn’t been for a chance encounter with an asteroid Earth would still be dominated by massive lizard-like creatures that had shown no inclination to build radio transmitters in the couple of hundred million years they were around. Unfortunately we have no idea how easy or inevitable the emergence of intelligent life with an interest in communications with aliens is. There is a temptation to say that Earth is a pretty ordinary planet, orbiting a pretty ordinary star, and ‘intelligent’ life emerged here, then it is likely to be commonplace across the galaxy. The counter argument is straight-forward: if it was uniquely difficult for such life to emerge, then that is where we live, because only where it emerges are the creatures able to ask such questions.
Shostak goes through the reasoning that the SETI Institute has gone through to decided what type of signals to listen in to and to analyse for signs of intelligent aliens. It has been a rigorously scientific approach. However the search is still considered a fringe activity and the Senate prevented NASA funding any further search after 1993 [p155]. Fortunately The SETI Institute had already been set up as a separate organisation and a well-connected fundraiser rang some of his contacts and raised enough cash to keep the show on the road. Most notably, Paul Allen, the co-founder of Microsoft, contributed, enough eventually to fund a dedicated radio telescope array. Shostak, writing around 2008, was hugely optimistic about the SETI Institute’s growing ability to search for signals, based on the old chestnut of Moore’s ‘Law’ leading to the perpetual exponential growth in computer performance and also planned expansion of the Allen telescope. Perhaps the 2009 financial crisis put a spanner in the works. The Allen telescope hasn’t been expanded and even the Arecibo telescope, then the world’s largest radio telescope has fallen into disuse. No signals from Aliens have yet been detected.
Shostak goes through other possible means that aliens might use to communicate, but all others are more problematic for us to detect. He also outlines a few solutions to the Fermi Paradox, where after discussing all the reasons why intelligent aliens should be plentiful, the brilliant scientist Fermi asked ‘where is everybody?’, i.e. why hadn’t humanity come across them. For a thoroughly comprehensive study of that question, see Stephen Webb’s excellent ‘Seventy-Five Solutions to the Fermi Paradox’ (reviewed on this site).
Shostak also touches on alien encounters and UFOs, exploring there scientific plausibility and dismissing them all as attention seeking, delusional, mistaken or paranoid. He takes an entirely rational approach to demolish all these claims. He also runs through what SETI does to eliminate strange signals that turn out to be either human made or entirely natural phenomena that require no intelligence. What would happen if the SETI Institute was convinced that it had found a signal generated by an intelligent alien? Shostak runs through the protocol of checks that would be international in scope, thus avoiding the question of surpassing such information by military or government. His experience with false signals suggests that the news of any plausible one would immediately be leaked to the media anyway.
Shostak writes well and the book is easy to read. There are occasional humorous and telling asides such as when someone claimed to have heard an alien signal and a radio talk-show host invited Shostak to call in: ‘Turning on the car radio to hear this sort of fare was like finding a horse head in your bed.’ [p206]. And ‘…although experts can be wrong, they’re more often right (which is what qualifies them for the soubriquet “expert” in the first place).’ [p237]. And ‘individuals could rapidly improve (unlike you, despite the urgings of your mother).’ [p272]. Fortunately he doesn’t over-do these witty asides.
This is an intelligently and rationally written account of the hunt by scientists for signs of intelligent aliens. It is an interesting and enlightening read about a subject that is all-too-often perverted by wackos.
Wikipedia biography of Shostak: https://en.wikipedia.org/wiki/Seth_Shostak
Others’ reviews of the book: https://www.goodreads.com/book/show/6294636-confessions-of-an-alien-hunter?ref=nav_sb_ss_1_23
© William John Graham, January 2024