Don’t laugh maybe every 20K years or so we have a large group of comets come in from the cloud with enough diffuse gas and dust to lower solar radiation reaching Earth causing an Ice Age
Or maybe we pass periodically through a band of gas and dust for the same effect.
“Don’t laugh maybe every 20K years or so we have a large group of comets come in from the cloud with enough diffuse gas and dust to lower solar radiation reaching Earth causing an Ice Age”
In planetary age measurement...that’s often!
We are above or below the galatic band and not as many dust particles and rocks and comets but like being at the beach by the ocean when you are laying down you notice the sand particles sandblasting you.
One day Earth will be sandblasted!