99% of the visible universe is made up of plasma, the fourth state of matter, generated when gases are energised. Plasma is abundant in geospace, the part of space engulfed by Earth’s magnetic field. When plasma is accelerated along the magnetic field and interacts with the atmosphere, one of the most impressive and well-known natural light shows on Earth is generated: the aurora. Whilst it is beautiful, the electric fields generated by the moving plasma have consequences for our modern lives.
Science