Astronomer Coryn A.L. Bailer-Jones proposes star triangulation as a reliable interstellar GPS in a new preprint. This innovative approach emerges as NASA develops pulsar-based navigation for deep-space missions, much like lighthouses guiding ships.
In 2018, NASA unveiled a space GPS alternative using pulsars—neutron stars that emit powerful electromagnetic radiation along their magnetic axes while spinning rapidly. This system aims to steer robotic spacecraft on missions far beyond human capability.
Within the Solar System, Earth-based signals effectively guide probes. But beyond the heliopause—where solar wind halts against the interstellar medium—signal round-trip times grow excessively long, creating a critical barrier for deep-space voyages.
NASA's X-ray pulsar method risks inaccuracies from signal scattering in the interstellar medium, warns Bailer-Jones of the Max Planck Institute. Such errors could undermine the pinpoint precision essential for navigation.
In his arXiv preprint, Bailer-Jones details a solution leveraging well-mapped stars and effects like parallax, aberration, and Doppler shift. These phenomena alter star positions and velocities as a spacecraft moves from the Sun, enabling adaptive triangulation that refines throughout the journey.
Simulations indicate that tracking about 20 stars delivers position accuracy within three astronomical units and velocity to 2 km/s. Incorporating more stars boosts precision further. While conceptual—given interstellar travel's remoteness—this represents a solid research direction.
