And here everything is very simple. When there is a lot of ionization and the molecules relative to you change the direction of their movement, the same effect occurs as with solar radiation. Charged objects (and molecules are also objects), moving relative to you with acceleration (and when the direction of movement changes as a result of collisions, the acceleration increases), begin to radiate. Well, I assume so.
In a kettle where water is boiled, the movement of molecules is accelerated. The kettle is a small accelerator of molecules. And you have in your Cup – hot tea that will emit in the infrared spectrum-relative to you.
Remember all the time. This radiation is relative.
Objects with respect to which the electric charge does not move with acceleration cannot receive its radiation either.
But back to the Sun.
Since the Sun radiates relative to us, it is radiation, though relatively, but objectively. This radiation knocks out some of the electrons (as lighter particles), which fly to the Earth and charge it negatively.
But does the number of electrons change from the point of view of a hypothetical observer, relative to which, neither the sun nor its molecules do not move with acceleration?
No, it does not change, because relative to this observer, the Sun does not emit or knock out a certain number of electrons.
Although it is difficult to imagine a frame of reference that is at rest relative to all solar molecules. But you don't need to submit it. Maybe there is no such system. But you need to know what's going on with such a system.
So we can say that the electrons flying towards the Earth are relative matter. But this relative matter is quite real for the Earth.
You, young people, better immediately get into the idea that all the substance:
a) is relative, not absolute;