What are the two factors which determine why some bodies in solar system have atmosphere and others do not?

Explanation

To determine why some bodies in the solar system have an atmosphere while others do not, we can analyze the two key factors involved:

### Step 1: Understand the Role of Gravity
The first factor is **acceleration due to gravity**. A body's ability to retain an atmosphere is significantly influenced by its gravitational pull.

- **Explanation**: A stronger gravitational force can hold onto gas molecules more effectively, preventing them from escaping into space. For example, larger planets like Jupiter have a much stronger gravitational pull compared to smaller bodies like Mercury, which allows them to maintain a thick atmosphere.

### Step 2: Consider Surface Temperature
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