Electromagnetic forces on a relativistic spacecraft in the interstellar medium

Abstract

A relativistic spacecraft of the type envisioned by the Breakthrough Starshot initiative will inevitably get charged through collisions with interstellar particles and UV photons. Interstellar magnetic fields would, therefore, deflect the trajectory of the spacecraft. We calculate the expected deflection for typical interstellar conditions. We also find that the charge distribution of the spacecraft is asymmetric, producing an electric dipole moment. The interaction between the moving electric dipole and the interstellar magnetic field is found to produce a large torque, which can result in fast oscillation of the spacecraft around the axis perpendicular to the direction of motion, with a period of $\sim$ 0.5 hr. We then study the spacecraft rotation arising from impulsive torques by dust bombardment. Finally, we discuss the effect of the spacecraft rotation and suggest several methods to mitigate it.

ApJ, in press; 9 pages, 6 figures

References in corpus (7)

• A terrestrial planet candidate in a temperate orbit around Proxima Centauri
• The Space Weather of Proxima Centauri b
• Subsonic Mechanical Alignment of Irregular Grains
• Prospects for Characterizing the Atmosphere of Proxima Centauri b
• The interaction of relativistic spacecrafts with the interstellar medium
• Deceleration of high-velocity interstellar photon sails into bound orbits at $\alpha$ Centauri
• Relativistic Gas Drag on Dust Grains and Implications

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