How does the solar wind affect a comet’s ion tail?

The solar wind plays a critical role in the formation and behavior of a comet’s ion tail, also known as a plasma tail or Type I tail.1

When a comet approaches the Sun, volatile gases in its coma are ionized through charge exchange with the solar wind. Once these molecules and free radicals become ionized, they are captured by the Sun’s magnetic field. The solar wind then carries these ions away from the Sun at high velocities—typically around 400 km per second—which is significantly faster than the comet's own orbital speed.12

Because of this high-velocity interaction, ion tails point almost directly away from the Sun. Occasionally, these tails may disconnect from the coma and fade as the comet crosses magnetic sector boundaries within the Sun’s magnetic field, after which the comet may begin to grow a new ion tail.12