Hatty Planets: Post Your Planet of the Hats Here

[Fred Brackin]

Originally Posted by tbrock1031

As a side note: I followed a few Wikipedia links and could not find whether the distance in AU from a start involved starts at the center or the "surface" of the star. This is especially notable when you consider that some giants (red and blue) have radii that can be measured in AUs.

It probably doesn't make much difference for a system like Sol, but for some other systems it might.

Stars much bigger than Sol don't have Earth-like planets. As size goes up lifespan goes down and probably much faster than you'd think. The largest blue giants (Type O) only spend 10 millions years on the main sequence before they go "Boom!". That's nt very long for forming even gaseous planets.

Those red giants aren't good places for planets either. The biggest ones were quite large (and therefore short-lived) as well and the wh0ole "expansion" thing does complicated but not good things to possible planets even if they had time enough for the rocky ones to cool.

You want a "hat"? You can use the "Famous Star Name Hat". Almost any star you've ever heard of will have been proved to be not good for planets. Invaders from Sirius anyone?