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Comment by blacksmith_tb | Hacker News Reader

I am not an astrophysicist, but I don't see any reason to doubt the study's conclusions. But isn't the more pressing question the probability of such a CME hitting the Earth? The sun is not small, and CMEs could be ejected away from it in any direction, I would think relatively few of them hit any of the planets?

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Kurzgesagt has a nice and objective summary on the topic. If I remember correctly, 50% chance of a big one hitting us over the next 50 years (or by 2050, can't remember exactly): https://youtu.be/oHHSSJDJ4oo

If it happens at night, you'll get a great lightshow to start off the apocalypse. From https://en.wikipedia.org/wiki/Carrington_event

>Auroras were seen around the world, those in the northern hemisphere as far south as the Caribbean; those over the Rocky Mountains in the U.S. were so bright that the glow woke gold miners, who began preparing breakfast because they thought it was morning.[8] People in the northeastern United States could read a newspaper by the aurora's light.[15] The aurora was visible from the poles to low latitude areas such as south-central Mexico,[16][17] Queensland, Cuba, Hawaii,[18] southern Japan and China,[19] and even at lower latitudes very close to the equator, such as in Colombia.

CMEs are not actually emitted uniformly over the whole spherical surface of the sun.

Instead it's much closer to a Gaussian distribution centered on the ecliptic.

For anyone not in the know, the ecliptic is the plane of the Earth's and most planets' orbit.

Is there any reason for that - gravitational forces from the planets perhaps?

Perhaps due to the sun's rotation?

I'd guess that it's related to the sun's rotation - the sun's equator roughly lies on the ecliptic.

https://en.wikipedia.org/wiki/Solar_rotation

I believe it is the fact that the solar system was once a spinning ball of gas and dust, and the spinning motion caused the cloud to flatten out into the protoplanetary disk. Like flattening a ball of pizza dough by spinning it in the air.

https://en.m.wikipedia.org/wiki/Protoplanetary_disk

https://www.vanderbilt.edu/AnS/physics/astrocourses/ast201/o...

When the solar system formed, the gas cloud collapsed along the shortest axis first into a spinning disc and then formed the planets and sun. This naturally aligns the largest bodies in most systems along the astral axis.

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