Hi, Erik;

I'll follow up on the previous replies, which focused on coronal mass ejections and the "storms" caused by plasma which is ejected from the Sun into the solar system. Accompanying these CMEs, and sometimes pretty much on their own, are solar flares -- which you could think of as primarily hitting the earth just with light. But that light is extremely energetic - some times it's visible light, but there are lots of x-rays and higher energy radiation coming from flares, which does impact the Earth. Flares cause disruptions in the upper layers of the Earth's atmosphere and bathes anything in orbit with pretty high doses of radiation. Because it is light, it goes out in all directions (compared to the mass from a coronal mass ejection, which is going to be pretty directed outward from a localized place on the Sun), so if we can see it, we've been"hit". And fast, too -- coronal mass ejections can take days to travel and impact Earth, however the solar flare x-rays come at the speed of light. So, in the "storm" analogy, the light and radiation from the solar flares are kind of like a lightning strike, and the coronal mass ejection is the hail. Which part of the "storm" you are most concerned with depends on which part will impact you more. Cheers,-KD