The aperture and focal length of the objective of telescope are large, why?

Explanation

To understand why the aperture and focal length of the objective of a telescope are large, we can break down the explanation into two parts: the significance of the aperture and the importance of the focal length.

### Step-by-Step Solution:

1. **Understanding Aperture**:
- The aperture of a telescope refers to the diameter of the objective lens or mirror. A larger aperture allows more light to enter the telescope.
- **Reason**: More light entering the telescope increases the intensity of the image formed. This is crucial for observing faint celestial objects, as it enhances the brightness and clarity of the images.

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