Astronomy and astrophysics are the studies of the solar system, the Sun and stars, galaxies , black holes , and the Universe as a whole. There is a big difference between the science of astrophysics and the other sciences, such as biology, chemistry and physics. While most scientists can perform experiments where they change the parameters of a system to see what the effect is, astronomers can only observe what is happening to the objects they study.
Most people take some science classes where they perform laboratory experiments.
You may have measured the acceleration of a small ball dropped from different heights in your physics class, or made simple circuits to study voltage, current and resistance. Maybe you studied how oxygen affects combustion in chemistry class. You might have looked at your own cells under a microscope in biology, or studied how animals react to different environments. Astronomers can't do this. They can't change the temperature of a star and see what happens.