"Things You Wouldn't Know If We Didn't Blog Intermittently."
Yep. Mercury has a stable 2:3 Spin-orbit resonance with the Sun.
Whoops. That ratio should be 3:2 not 2:3.
Sufferers of 'Seasonal Affective Disorder' (SAD) should avoid Mercurean nights, then....
I'm 257 Mercury years old and this is the first time I've heard of this.