Astrophysics is a branch of astronomy that deals with physics of the universe. It looks at the physical properties of celestial objects and their interactions and behaviors. The objects studied are stars, plants, galaxies, the interstellar medium and the cosmic microwave background. The object's emissions are examined across the electromagnetic spectrum. The properties examined are luminosity, density, temperature and the chemical composition.
Astrophysics has a wide range of research areas. Astrophysicists’ are specialize in many different areas such as, mechanics, thermodynamics, quantum mechanics, electromagnetism, and particle physics. Astrophysics is a sub-discipline of atmospheric physics which looks at the upper layers of the atmosphere where dissociation and ionization principles are important.
Atmospheric physics is the application of physics to study the atmosphere. This is done by using the fluid flow equations, chemical models, radiation balancing and energy transfer processes in the atmosphere. Physicists link meteorology and climatology by using cloud physics, statistical mechanics and spatial statistics to model weather systems. Atmospheric physicists also designs and constructs instruments used to study the atmosphere. Atmospheric physics and environmental science are closely related.