Dec 27, 2025 12:00:00

If SETI is successful and discovers an extraterrestrial civilization, what should we do?

The Search for Extraterrestrial Intelligence (SETI), the attempt to search for extraterrestrial civilizations on Earth, is both a dream for humanity and a major research topic. But what if SETI proves successful and we do discover an extraterrestrial civilization? Andrew Tomaswick , chief design engineer and writer for the International Academy of Astronautics (IAA) , shared his answer to that question in a post on the space and astronomy news site Universe Today .

What Do We Do If SETI Is Successful? - Universe Today
https://www.universetoday.com/articles/what-do-we-do-if-seti-is-successful

From its early days of monitoring extraterrestrial radio communications to examining the use of interstellar lasers and detecting signs of Dyson swarms , SETI has expanded its knowledge of how to detect intelligent life in our galaxy, and the IAA is currently updating its protocols for what researchers should do once intelligent life is discovered.

The proposed new protocol has been published as a preprint on arXiv and is expected to be adopted at

the International Astronautical Congress (IAC) in Sydney in 2025, with formal adoption expected in early 2026. If the protocol is updated, it will be the largest change in the 36-year history of the IAA, since it first formulated its 'Statement of Principles' in 1989. The proposed update includes several key points, reflecting the ever-increasing complexity of dealing with highly sensitive topics in modern society, especially on social media. The majority of the updates are intended to protect researchers from online harassment and beyond.

However, if there is one change that is most important, it is the suggestion that researchers should not reply to direct messages from extraterrestrial intelligent life .

The previous protocol stated that 'messages should be responded to,' and therefore placed few restrictions on responses. The updated protocol, on the other hand, proposes that researchers should not respond to messages at all until discussions have taken place in an external international organization such as the United Nations. This proposal does not directly affect the METI ( Message to Extraterrestrial Intelligence ) initiative. While some kind of protocol is considered necessary for METI, at present, only position papers have been presented by the IAA and other organizations, and no officially adopted protocol exists.

The new SETI protocols specify how to verify extraterrestrial signals and collected data, how to store the data in two geographically separate locations to make it accessible to a wider range of interested parties, and the software used to analyze the data. Furthermore, if the signal is electromagnetic, the paper suggests petitioning the International Telecommunication Union (ITU) to request the release of the frequency band in which the signal is detected. Note that these protocols are not binding rules, but should be considered merely 'best practices.'

'This update shows that the world has become incredibly complex over the last 15 years, from the political and social environment to what a SETI discovery might mean,' Andrew said. 'While no one has the perfect answers for what we should do if we discover a signal that suggests the presence of extraterrestrial intelligence, the IAA's approach to updating its protocols is exemplary.'