Here's a breakdown:

* Newton's Law of Universal Gravitation: This law states that every particle in the universe attracts every other particle with a force that is:

* Proportional to the product of their masses: The more massive the objects, the stronger the gravitational force.

* Inversely proportional to the square of the distance between them: The farther apart the objects, the weaker the gravitational force.

* Sun and Earth: The sun is incredibly massive compared to Earth, and even though they are far apart, the gravitational force between them is significant. This force keeps Earth in orbit around the sun.

Calculating the Force:

You can calculate the force of gravity between the sun and Earth using the following formula:

```

F = G * (m1 * m2) / r²

```

where:

* F is the force of gravity

* G is the gravitational constant (approximately 6.674 x 10⁻¹¹ N⋅m²/kg²)

* m1 is the mass of the sun (approximately 1.989 × 10³⁰ kg)

* m2 is the mass of the Earth (approximately 5.972 × 10²⁴ kg)

* r is the distance between the centers of the sun and Earth (approximately 149.6 million km)

Magnitude of the Force:

The force of gravity between the sun and Earth is approximately 3.54 x 10²² Newtons (N). This is a massive force, but it's balanced by Earth's orbital velocity, preventing Earth from falling into the sun.