[ETL]

Seems it's not the Sun ~ rather SUPER NOVAS

The theory is it's galactic cosmic rays emitted by distant super novas. The galactic cosmic rays help promote cloud formation and COOLING on Earth. The sun's magnetic field acts to repel GCRs, more or less depending on the current level of solar activity. More sunspots = less low-lying, thick cumulus, cooling-effect clouds = warmer temps

[muawiyah]

The Sun's magnetic field goes through cycles ~ short duration compared to "density of Super Nova explosions" ~ those seem to be based on where in the arm you are, and how high above or below the plain of the ecliptic you might be ~ some places are, with some regularity, hotter and nastier than others.

Enough cosmic rays are produced to simply overwhelm the puny efforts of the Sun ~ and we end up with lots of ice and stuff ~ and fewer species!

Looking at the chart it appears we are heading into another band of Super Novas ~

This knowledge helps us understand where in this and other galaxies life can survive for long enough to come up with some good thoughts and neat inventions.