Method and experiment
The experimental method is based on a principle : it is to change a set of parameters using an experimental device designed to allow control of these parameters in order to measure their effects and if possible to model. In the simplest case one tries to change one parameter at a time. The experimental protocol includes the description of the conditions and the course of an experiment or a test. The description must be sufficiently clear so that the experience can be reproduced identically and must be critically analyzed to detect any particular bias. |  |
Question
Explain why we must plan our experiment before doing it, in astronomy for example?
What does it involve? (=What are the consequences?)
(Length of your answer from 2 to 5 lines)
