How does the close proximity of Mercury to the sun affect its characteristics and behavior?

Oh honey, if I had a dollar for every time someone asked me that! Here's the deal - because Mercury is practically hugging the sun, it gets baked. I mean, we're talking about temperatures hot enough to fry an egg on the sidewalk - except this sidewalk is a planet. So yeah, the heat warps its atmosphere, makes its surface all cratered and wrinkly, and basically turns it into a little badass planet with attitude.