In regards to naked-eye viewing, the rule of thumb I heard is that if you have to squint, look away.

Interesting, the rule of thumb I heard is don't.

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Howling from the Shadows

It must be fun to lead a life completely unburdened by reality. --- JayUtah

You can't reason an irrational person out of an irrational belief. --- Noclevername

Apollo: The History and the Hoax
Enter the World of Athran