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Comment by h2odragon | Hacker News Reader

When does the mega sunspot or whatever hafta fire a large mass ejection at us, and how strong would it have to be, to cook most of humanity?

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To cook us, it would have to be stronger than is actually possible given the mass, distance, and age of the sun.

To cook our power grid, small enough to be surprisingly common: https://en.wikipedia.org/wiki/List_of_solar_storms

The sun fires multiple ejections a day big enough to cook us. They just all miss.

It would be like you stepping outside and shooting a bullet in a random direction a few times a day, with Earth being a golf ball miles away.

The golf ball would be destroyed by a bullet. But your odds of hitting it are very low.

Of course, over time the odds become an inevitability.

Your metaphor is totally off. For one thing, even the biggest CMEs aren't powerful enough to literally cook us. Partly because of solar size, distance and composition, and partly because our Earth has its own protections via the atmosphere, our robust electromagnetic field and a few atmospheric factors. Secondly, random bullets fired off in random directions remain as small dense objects. That metaphor works better for asteroids randomly bounding around the solar system. CMEs on the other hand expand and spread to pretty huge sizes as they fly outward into the Solar System. This makes them much more likely to arrive.

Why do people just make up things like this? Did you hear it somewhere and never research it?

Why is this downvoted? Is it wrong? I do like it as an explanation!

Yeah, it's wrong. There isn't even a single CME strong enough to cause aurora every day, let alone strong enough to cook us, and let alone multiple times per day.

It is wrong. During the peak of the solar activity cycle, the sun produces about 3 coronal mass ejections a day. During the bottom of the cycle, though, it only produces one about once every 5 days. They do sometimes hit the Earth, too. The largest known was the Carrington Event in 1859, which started some of the US telegraph network on fire. There was one in 1989 as well.

I don't know that there has ever been a CME strong enough to cook all animals on the side of Earth facing the sun, though. The sun is pretty far away and Earth has a nice magnetosphere that is one of the reasons life exists in the first place. It protects us from stuff like this.

Incidentally, a CME cooking the entire Earth was the plot of a pretty terrible Nic Cage movie called Knowing a decade or so back.

I'm not sure about the cooking power but in terms of the scale of things, if the earth were a golf ball, a 2000km wide coronal mass ejection would indeed be like shooting a bullet in a random direction at a golf ball half a kilometer away.

Can't wait

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