Neptune is the eighth planet in our Solar System. It is positioned between Uranus and Pluto, and is sometimes called the Blue Giant. The planet is nearly 49,500 kilometers in diameter, making it nearly 4 times the size of our planet, Earth. Also, Neptune is situated around 4.4 billion kilometers from Earth, and therefore, it is not visible to naked eyes. Even using binoculars, you will not be able to see the planet clearly.