What do you call an object that shows what something looks like that is too big too small or too old to be studied?

An object that represents something too big, too small, or too old to be studied directly is called a "model." Models can be physical representations, like scale models, or conceptual, like simulations, that help visualize and understand complex phenomena or objects. They are widely used in fields such as science, engineering, and architecture to facilitate analysis and communication.