Neptune was observed in 1613 by Galileo Galilei however, he taught that it was just a star, and when he wanted to further research it, the motion of the planet began to be far too slight to be detected again. Due to its size it is even believed it is a captured dwarf planet. This means that it is a captured object by Neptune’s gravity. Neptune also has 14 known moons, the largest is called Triton, and it is the seventh largest known moon of any planet, also being the only one in the solar system that orbits in retrograde or in opposition to the planet’s rotation.

Neptune has a total of 6 known rings with some containing ring arcs or clusters of dust particles in a ring.Most winds travel retrograde to the rotation of the planet they are 5 times stronger than the strongest winds recorded on Earth, breaking the sound barrier. Wind speeds blowing westward on the equator reach up to 2,160 kilometers or 1.324 miles per hour, nearly a supersonic flow. It has the fastest wind speed of any planet. Neptune however, excels from something else.It has an average temperature of -214 degrees Celsius -353 degrees Fahrenheit, however Uranus is the coldest ice giant, and for that fact the coldest of all planets in the solar system.Neptune is the smallest ice giant with a mass of 1.024 × 10^26 kg but has the greatest density out of all the gas giants, about 1.64 g/cm³.This is a characteristic of the ice giants, their “rocky”, icy cores who are proportionally larger than the amount of gas they contain, unlike the gas giants.It has a core about 1.5 times the size of Earth with twice its pressure: 7 Mbar or 700 GPa, making up about 45% of the planet’s mass, but it does not have a surface.Neptune being made out of layers of helium 29% and 80% hydrogen with traces of methane. Neptune and Uranus are termed as ice giants because they are smaller and have different compositionality from the gas giants Jupiter and Saturn.Neptune has a radius of 15.387 miles or 24.764 kilometers, about four times wider than Earth, and a diameter of 49.244 km or 30.598 mi being the fourth largest planet of the solar system.Until Pluto’s eccentric orbit was understood and its status dropped from that of a planet to a dwarf planet, Neptune was considered the second furthest planet from the Sun.However, one rotation or day on Neptune is completed in 16 hours.As a result from its distance, it also has the longest orbital duration completing a trip around the Sun in about 165 years.Neptune’s actual position can be checked online as the planet is constantly tracked. Currently it is 29.4 AU away from Earth with its light taking up to 4 hours to arrive to us. Neptune has an average distance of 2.8 billion miles/4.5 billion kilometers or 30 AU away from the Sun, being the furthest of the eight planets.Neptune’s color is believed to be influenced by the presence of methane in its atmosphere and also an unknown factor.Its satellites also received names of water deities. Neptune was given the name of the roman god of the sea due to its bluish-ocean like color.He predicted where it should be, and astronomer Johann Galle found it one degree away from the predicted point thus making Neptune the first planet to be discovered by mathematical calculations and predictions. The perturbed orbit of Uranus forced astronomer Urbain Le Verrier to conclude that another undiscovered planet must be at fault.The greatest factor of the discovery was the planet Uranus, whom astronomers were calculating its orbit and observed that Uranus wasn’t following their models.It is the only planet that is invisible to the unaided eye, thus it eluded ancient astronomers until it was officially discovered in 1846 by Le Verrier and Johann Galle.

Neptune space