During a space mission, scientists will send experiments for the astronauts to conduct in space. In many cases, scientists have made predictions about the outcome of the experiment. Why do astronauts perform the experiment if the results have already been predicted?

The questions have been asked in several important state and regional science exams in the United States. For example: TAKS-Texas Assessment of Knowledge and Skills, New York State Educational Department Regents exams, California Standards Test, etc.