Even Earth’s mightiest telescopes aren’t up to the task of imaging Apollo lunar landing sites. A lack of resolution is the biggest reason why

Magnification is just how much you can zoom in on an object, making it look bigger. That’s important because while astronomical objects are physically big, they’re very far away, so they appear small in the sky. Magnifying them makes them easier to see.

Resolution, on the other hand, is the ability to distinguish two objects that are very close together. For example, you might perceive two stars orbiting each other—a binary star—as a single star because they’re too closely spaced for your eye to separate. You can’t resolve them. Looking through a telescope with higher resolution, however, you might be able to discern the separation between them, revealing that they are two individual stars.

But isn’t that just magnification, then? No—because magnification only makes things bigger!