# Pulsar Positioning System: A quest for evidence of extraterrestrial engineering

## TL;DR

This paper explores the potential of pulsar-based navigation as a galactic-scale positioning system and investigates whether it could be evidence of extraterrestrial engineering, proposing a SETI research program to test this hypothesis.

## Contribution

It introduces the SETI-XNAV research framework to evaluate if pulsar signals are artificially engineered by extraterrestrial civilizations.

## Key findings

- Pulsars could serve as galactic navigation beacons.
- The distribution and properties of pulsars may indicate artificial origin.
- Pulsar signals might contain encoded information or synchronization cues.

## Abstract

Pulsars have at least two impressive applications. First, they can be used as highly accurate clocks, comparable in stability to atomic clocks; secondly, a small subset of pulsars, millisecond X-ray pulsars, provide all the necessary ingredients for a passive galactic positioning system. This is known in astronautics as X-ray pulsar-based navigation (XNAV). XNAV is comparable to GPS, except that it operates on a galactic scale. I propose a SETI-XNAV research program to test the hypothesis that this pulsar positioning system might be an instance of galactic-scale engineering by extraterrestrial beings (section 4). The paper starts by exposing the basics of pulsar navigation (section 2), continues with a critique of the rejection of the extraterrestrial hypothesis when pulsars were first discovered (section 3). The core section 4 proposes lines of inquiry for SETI-XNAV, related to: the pulsar distribution and power in the galaxy; their population; their evolution; possible pulse synchronizations; pulsar usability when navigating near the speed of light; decoding galactic coordinates; directed panspermia; and information content in pulses. Even if pulsars are natural, they are likely to be used as standards by ETIs in the galaxy (section 5). I discuss possible objections and potential benefits for humanity, whether the research program succeeds or not (section 6).

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Source: https://tomesphere.com/paper/1704.03316