what do mechanical and aerospace engineers do?

Mechanical engineers design tools that other engineers need for their work. It is one of the broadest engineering disciplines. Mechanical engineers work on power-producing machines such as generators, engines and turbines, and they also work on power-using machines such as refrigeration and air-conditioning equipment, machine tools, material handling systems, elevators and escalators, industrial production equipment, and robots used in manufacturing. Aerospace engineers develop new technologies for use in aviation, defense systems, and space exploration. They may become experts in aerodynamics, thermodynamics, celestial mechanics, propulsion, acoustics, or guidance and control systems. Source: U.S. Department of Labor Bureau of Labor Statistics