Relative Likelihood of Success in the Searches for Primitive versus Intelligent Extraterrestrial Life

TL;DR

This paper compares the likelihood of success in searching for primitive versus intelligent extraterrestrial life, emphasizing the importance of concurrent searches and proposing increased funding for SETI based on current biosignature efforts.

Contribution

It provides a quantitative analysis of search volumes and success probabilities, recommending a significant increase in SETI funding based on current biosignature research.

Findings

Search volume for artificial signals is larger than for biosignatures.

Concurrent searches for primitive and intelligent life are recommended.

SETI funding should be at least $10 million annually.

Abstract

We estimate the relative likelihood of success in the searches for primitive versus intelligent life on other planets. Taking into account the larger search volume for detectable artificial electromagnetic signals, we conclude that both searches should be performed concurrently, albeit with significantly more funding dedicated to primitive life. Based on the current federal funding allocated to the search for biosignatures, our analysis suggests that the search for extraterrestrial intelligence (SETI) may merit a federal funding level of at least $\$10$ million per year, assuming that the average lifetime of technological species exceeds a millennium.