One of the primary open questions of astrobiology is whether there is extant or extinct life elsewhere the Solar System. Astrophysicists Avi Loeb at Harvard and Penn State’s Jason Wright have both explored the question, with Loeb suggesting that ancient technological artifacts from beyond the Solar System may exist on Earth’s Moon amounting to a letter from an alien civilization saying, “We exist.”

Wright, a member of  the Center for Exoplanets and Habitable Worlds, has considered the possibility that a technological species could have existed in the Solar System prior to humanity’s rise on Earth in his study, Prior Indigenous Technological Species.

In 2016, Wright authored a paper that discussed possible origins and locations for “technosignatures” of such a civilization while other astronomers have suggested looking for lights on Kuiper Belt Objects that “may serve as a lamppost which signals the existence of extraterrestrial technologies and thus civilizations.”

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