Weegy: The coldest layer of the atmosphere is the mesosphere User: _____is the hottest layer in the atmosphere. User: what is the hottest layer in the atmosphere. Weegy: The thermosphere is the "hottest" layer of the Earth's atmosphere. [ As the outermost layer with substantial numbers of molecules, it receives the most direct radiation from the Sun.
However, despite the high molecular temperatures measured there (over 1500°C) the ... (More)