Why is there such a large range of temperature on mercury?

Answer 1

well its close to the sun and has no atmosphere and no magnetosphere so the sun scorches the planet all day which by the way lasts approximately 90days as the orbit about its on axis is so slow that Mercury has a day longer than its year like Venus, also when not facing the sun the other half of Mercury again because of its lack of atmosphere is exposed to temperatures of a few degree's above absolute zero this means that much like the Sahara desert it has very hot days and freezing cold nights.

Answer 2

because mercury is not really tilted like the earth, it is pretty much up and down. so when one side is facing the sun, it is really hot, and when the other part of the planet is facing away from the sun, it is really cold, and it does not have an atmosphere, so when its facing away from the sun, no heat is really trapped in. hope that helped :)