Electric sails are potentially more effective than light sails near most stars

TL;DR

This paper compares electric sails and light sails for stellar propulsion, finding electric sails more effective near most stars, especially M-dwarfs, and proposes a method to enhance light sail speeds for interstellar travel.

Contribution

It provides a comparative analysis of electric and light sails across different star types and introduces a strategy to boost light sail speeds via multiple stellar encounters.

Findings

Electric sails can reach ~500 km/s near M-dwarfs.

Light sails are ineffective around late-type M-dwarfs due to low radiation pressure.

Repeated stellar encounters could accelerate light sails to >0.1c.

Abstract

Electric sails are propulsion systems that generate momentum via the deflection of stellar wind particles through electric forces. Here, we investigate the relative merits of electric sails and light sails driven by stellar radiation pressure for F-, G-, K- and M-type stellar systems. We show that electric sails originating near M-dwarfs could attain terminal speeds of $\sim 500$ km/s for minimal payload masses. In contrast, light sails are typically rendered ineffective for late-type M-dwarfs because the radiation pressure is not sufficiently high to overcome the gravitational acceleration. Our analysis indicates that electric sails are better propulsion systems for interplanetary travel than light sails in proximity to most stars. We also delineate a method by which repeated encounters with stars might cumulatively boost the speeds of light sails to $\gtrsim 0.1\,c$, thereby making them more suitable for interstellar travel. This strategy can be effectuated by reaching $\sim 10^5$ stars over the span of $\sim 10$ Myr.