Aurora on Earth are caused by particles from the Sun interacting with our planet’s protective magnetic field. Without that magnetic field on Earth, we would not be here. All life is entirely dependent on the shielding that our magnetic field provides. So if we are to search for life elsewhere, one good way to separate out those planets that may harbor life from those that do not, will be to search for Aurora. Except we’re not at the stage in our technology where we can image planets around other stars well enough to see aurora. So we have to find another way.
Luckily, the aurora also produces radio waves. So instead of watching, we can listen.
ET is not phoning home, but we are hearing the potential for life in our solar system