Prior Indigenous Technological Species (1704.07263v2)

Abstract: One of the primary open questions of astrobiology is whether there is extant or extinct life elsewhere the Solar System. Implicit in much of this work is that we are looking for microbial or, at best, unintelligent life, even though technological artifacts might be much easier to find. SETI work on searches for alien artifacts in the Solar System typically presumes that such artifacts would be of extrasolar origin, even though life is known to have existed in the Solar System, on Earth, for eons. But if a prior technological, perhaps spacefaring, species ever arose in the Solar System, it might have produced artifacts or other technosignatures that have survived to present day, meaning Solar System artifact SETI provides a potential path to resolving astrobiology's question. Here, I discuss the origins and possible locations for technosignatures of such a $prior$ $indigenous$ $technological$ $species$, which might have arisen on ancient Earth or another body, such as a pre-greenhouse Venus or a wet Mars. In the case of Venus, the arrival of its global greenhouse and potential resurfacing might have erased all evidence of its existence on the Venusian surface. In the case of Earth, erosion and, ultimately, plate tectonics may have erased most such evidence if the species lived Gyr ago. Remaining indigenous technosignatures might be expected to be extremely old, limiting the places they might still be found to beneath the surfaces of Mars and the Moon, or in the outer Solar System.

• The paper proposes searching for evidence of a prior indigenous technological species within the Solar System by looking for durable technosignatures on various celestial bodies.
• It highlights that Earth's geological activity makes preserving ancient technosignatures difficult over long timescales, suggesting other solar system bodies may be better candidates for detection.
• The research suggests new directions for astrobiological search, such as artifact SETI, and implies that technological evolution could have occurred and ended before humanity arose.

Analysis of Prior Indigenous Technological Species within the Solar System

The paper by Jason T. Wright explores the hypothetical scenario of a prior indigenous technological species that may have arisen in our Solar System. This inquiry probes the potential existence of such species, which may have left technosignatures—observable signs of technological activities—on Earth or other celestial bodies within the Solar System. The discourse contributes a novel perspective to the field of astrobiology, diverging from the traditional exogenous origin search strategies commonly associated with SETI (Search for Extraterrestrial Intelligence).

Technological Artifacts and Erasure Timescales

Wright evaluates the possibility of detecting technosignatures, noting that Earth is a particularly challenging environment for preserving such evidence over geological timescales. Plate tectonics and erosion continually recycle Earth's surface, likely erasing most technosignatures of any ancient civilization. However, certain artifacts such as isotopic anomalies from nuclear activities or resource depletion from extensive mining could potentially serve as long-term markers of a technology's existence.

The Earth's oldest rocks might yield signs of past technology, albeit their detection would be challenging due to natural processes. Wright suggests that exploring these scenarios on other planetary bodies—where erosion processes differ significantly from Earth's—could be more fruitful.

Potential Sites Beyond Earth

Wright considers several potential sites for discovering ancient technosignatures, including Mars, Venus, and icy moons. Ancient Mars, with evidence of past liquid water, and a thinner-atmosphere Venus could have hosted ancient life capable of developing technology. However, obstacles such as dust erosion on Mars or catastrophic resurfacing on Venus could limit technosignature preservation. The author also entertains scenarios on asteroids and other moons, where artifacts could persist longer in stable, less erosive conditions.

Implications for Astrobiological Research

The implications of this paper are twofold. Practically, it suggests new avenues for artifact SETI, urging exploration for technosignatures that would ordinarily be overshadowed by the search for microbial life. Theoretically, it challenges the notion of a singular technological evolution by proposing that an indigenous technological species could have existed and become extinct before human civilization, potentially resetting life's technological progress on Earth or elsewhere.

Future Directions

Explorations into Venus’s geological history, pre-Cambrian Earth, and artifacts near the Solar System’s least disturbed regions are proposed as promising routes to either support or refute this hypothesis. Additionally, understanding the long-term stability and collision rates of free-floating artifacts in non-Earth environments could provide further clarity. Wright’s paper encourages the integration of techniques from planetary geology and archeology to detect these elusive markers, offering a multidisciplinary approach towards a deeper understanding of technological life’s potential prehistory within our cosmic neighborhood.

This comprehensive exploration of indigenous technological species within the Solar System highlights the need for extending our search and understanding of life and intelligence beyond Earth, pushing the boundaries of how and where we might uncover evidence of past technological civilizations.