Harvard Astronomer Says Mankind Will Go Extinct From 'Self-Inflicted Wounds' Long Before Sun Engulfs Earth

The chair of astronomy at Harvard University has said our civilization will probably go extinct from "self-inflicted wounds" long before the sun's eventual demise poses a threat to Earth.

Avi Loeb, who is also the founding director of the Black Hole Initiative at Harvard and has an advisory role on the Breakthrough Starshot project, was asked by a journalist on how to best protect humanity from the long-term risks facing our planet, such as what will happen when the sun boils away Earth's oceans about a billion years from now.

In an opinion article for Scientific American, Loeb said there are lots of options for protecting humanity against the initial threat posed by a brightening sun, including those being looked at to limit the impact of global warming. Later on, he said we would need to create a "gigantic structure" that could be moved to an optimal orbital distance.

"Since modern humans needed merely 100,000 years to adapt from living in the savannahs and forests of Africa to squeezing into a tiny apartment in Manhattan one can reasonably expect them to transition from Manhattan to living in space over a time span that is ten thousand times longer," he wrote.

Ultimately, our star will one day die, engulfing Earth in the process. To save mankind, Loeb wrote, humans must look to planets elsewhere in the universe. He said humans should make "genetically identical copies" of the animals and plants we want to keep and spread them out to other star systems. This would lower the risk of complete "annihilation" from a single catastrophe. Eventually, mankind could send out the tools needed to build humans from the raw materials on multiple planets. This would remove the need for humans traveling extreme distances to new planets, but would still preserve the species.

"The instinct of any parent is to care for the offspring and secure longevity this way; nature enabled us to extend the lifetime of our genome well beyond our own life span in this way," Loeb wrote. "As an extension, modern science might enable us to construct printers that are capable of mass-producing copies of ourselves on other planets by merely exporting our genetic blueprint without requiring that our bodies will physically travel the distance. We should be satisfied with this renewed sense of security and retire happily when our mission is accomplished...Perhaps we already are one copy out of many in existence, so it is not essential for this copy to survive."

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Image showing a giant solar prominence on the sun. In about a billion years the sun will get brighter, eventually causing all the water in Earth's oceans to evaporate. NASA Goddard

Loeb is one of the scientists who made global headlines in recent years after discovering the interstellar visitor 'Oumuamua. One controversial idea that the team put forward was that 'Oumuamua was an alien spaceship sent out by an advanced extraterrestrial civilization to analyze our star system. This has now been largely dismissed.

In his Scientific American article, Loeb discusses the possibility of any civilization, including our own, reaching the point where it could consider settling on other planets. "After reading this morning's newspaper, I am inclined to believe that our civilization will disappear as a result of self-inflicted wounds long before the sun will pose its predictable threat," he wrote. "Why do I believe that? Because the dead silence we hear so far from the numerous habitable exoplanets we've discovered may indicate that advanced civilizations have much shorter lives than their host stars."