Total Eclipse by John Brunner
The story works under the premise that none of Earth's nations - with their conflicts, excess populations and other issues - were able to have their own interstellar exploration programs. The UN, with funds from various nations, built one starship and sent it on a number of voyages. One of the main hopes was that other civilizations would be found. No evidence of other intelligent races was found - until Sigma Draconis. There ruins were found of a civilization that disappeared 100,000 years ago. Scientists are sent there to try to understand what happened. Years passed and the scientists collected data, but real understanding eluded them.
Apparently, the aliens rose from the Stone Age to the space age in just 3000 years, then suddenly civilization broke down and the species became extinct. The aliens were very different - crab-like beings with an electromagnetic sense.
As the years pass, Earth began to begrudge the money spent on this project and became suspicious of what was really happening. When the starship returns to Sigma Draconis, it is not only carrying new scientists to replace those who will be going home. There is also an investigator aboard who has been sent to find out what is going on. Is the project just a scam? Have they found alien weapons which will be used to control Earth? The people of Earth have begun to think more in these ways as conditions on Earth deteriorate towards wars and other crises.
One of the newly arrived scientists, Ian, was very good on Earth at making sense of inscriptions left by disappeared ancient societies on Earth. Ian becomes the central character of the story and plays a major role in new ideas for researching the alien's civilization. The aliens' electromagnetic sense appears to have lead to them storing material on crystals with certain electromagnetic properties. At least some of those are presumably degraded over time. In any case, it's not really known what is stored in them - books, pictures, music, emotional states or what. The scientists believe the aliens sensed the electromagnetism emanating from each other, leading to an inability to lie, a feeling of being cut off if buildings blocked them from sensing others, etc.
Ian has the idea of making a replica of an alien that a human can be inside and through which experience the world in a way similar to what the aliens experienced. He suggests this would give humans insights that could help them understand the aliens.
Throughout the book the scientists struggle with the mysteries of the dead alien civilization, and struggle with doubts about the future of Earth. And those doubts make them worry whether crises on Earth will prevent the starship from returning for them. As the amount of data about the alien ruins (and some alien corpses) grows, more questions are added than are answered. The scientists conceive of more alternatives of what might have happened to the aliens, but they don't have what they need to disprove many of the possibilities. More of the scientists come to place their hopes on Ian's ability for insights and the potential for increasing understanding when Ian lives inside the artificial alien body.
Ian gets into the artificial alien body and goes off to a site away from humans (to help him not think about humans or in human terms). After he has done this for weeks, he is brought back to the human settlement after the medical monitors show he is sick and fevered. When Ian comes to he is upset that his experiment was interrupted - he insists he was just at the point of understanding what happened to the aliens, but now he can't recall what it was. He works at trying to jog his memory for days, with no success.
To some extent, this presents a view of another kind of alien. Of course, it can be somewhat gloomy exploring an extinct intelligent race. And even more if the human race isn’t doing so well in the story either. One might think of this as an exploration of the various ways civilizations might fit into the self-destruction solution to the Fermi Paradox. Perhaps Brunner is asking the question, “How can we be so smart, yet be so dumb.”
I don’t consider Total Eclipse to be one of Brunner’s best done novels, but it is decent. It is also on the short side.
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