Question

what did isaac newtons law of universal gravitation explain? *
why the earth revolves around the sun.
why the planets are different sizes.
why the stars twinkle.
why the moon has phases.

Explanation:

Newton's law of universal gravitation describes the gravitational force between two masses. It explains the orbital motion of the Earth around the Sun due to the gravitational pull between them. The other options are not related to this law. Planetary sizes are determined by formation - related processes, star - twinkling is due to atmospheric effects, and moon phases are due to the relative positions of the Earth, Moon and Sun.

Answer:

Why the Earth revolves around the Sun.