Cosmic radiation does not prevent collisional charging in (Pre)-Planetary Atmospheres

TL;DR

This study investigates whether cosmic radiation affects the electrical charging of dust and sand grains in (pre)-planetary atmospheres, finding minimal impact despite increased radiation levels at higher altitudes.

Contribution

The paper presents an experimental approach during a stratospheric balloon flight to assess cosmic radiation's influence on grain charging in planetary atmospheres.

Findings

Cosmic radiation increases by a factor of 54 with altitude.

Grain charges decrease by only up to 30% despite increased radiation.

Charge processes in planetary atmospheres are largely unaffected by cosmic radiation.

Abstract

In (pre)-planetary environments, dust and sand grains regularly collide. They electrically charge and discharge during these events. In this work, we study if cosmic radiation has any influence on the equilibrium charge state on timescales of minutes. We developed an experiment that was carried out during the ascent of a stratospheric balloon. With increasing altitude, the radiation activity increases by a factor of 54. However, we found only a very minor decrease in grain charges of up to 30%. This implies that charge-moderated processes from thunderstorms on Earth, over early phases of planet formation to particle motion on the Martian surface on short timescales essentially proceed unhindered from a direct influence of cosmic radiation.