It's possible you're asking about one of the following:
* The mesosphere of Earth's atmosphere: This is a layer of the atmosphere located between the stratosphere and the thermosphere. It's characterized by decreasing temperature with increasing altitude.
* The surface of the mesosphere: This is a bit ambiguous. There isn't a hard "surface" to the mesosphere, as it blends into the thermosphere.
Could you please clarify your question? Do you want to know more about the mesosphere of Earth's atmosphere? Or are you asking about something else entirely?