Why is Mercury called the planet of extremes?

Answer 1

most likely because of the extreme temperatures its like boiling during the day and freezing at night you also can't live on it unless you want to die but if you do want to die don't waste billions of dollars for someone to throw you on Mercury call decsnigg111 he'll take care of it( I'm not kidding he's already killed 5 people)

Answer 2

Mercury is called the planet of extremes because it experiences the largest temperature variations of any planet in our solar system, with temperatures reaching up to 800 degrees Fahrenheit on its sunlit side and dropping to -290 degrees Fahrenheit on its dark side. Additionally, it has the greatest temperature difference between day and night due to its thin atmosphere which does not retain heat well.