How Does a Tiny Dot's Mass Distort Space Time?

[Intuitive]

Quiz Question.

Let say we had a piece of Matter the size of a Dot like the size of a Period at the end of a Sentence ^3, How heavy would this Dot have to be before it begins to seriously distort Space Time?

 

[SpaceTiger]

Newtonian gravity would become a poor approximation as the dot approached a mass for which its radius was near the Schwarzschild radius. For an ordinary period at the end of a sentence (few tenths of a millimeter), this would be about the mass of the moon.