Orbital Characteristics

 Distance from star:

Neptune orbits the Sun at an average distance of 30.1 AU completing one orbit every 164.8 Earth years.

Its orbit is nearly circular with a low eccentricity of 0.0086-0.0113, so perihelion reaches 29.81 AU and aphelion just 30.33 AU- minimal variation compared to more elliptical planets like Pluto. Inclined 1.77 degrees to the ecliptic, it moves slowly at 5.43 km/s average velocity.

The vast distance delivers only 1/900 Earth’s solar energy, causing frigid temperatures (~59 K at cloud tops0 and faint sunlight, yet internal heat dominates, fueling supersonic winds and storms. Long year creates 40-year seasons due to its 28-degree axial tilt, while shaping the Kuiper Belt via resonances that clear gaps beyond 30 AU.

Orbital Period: Neptune’s orbital period, or length of its year, is 164.8 Earth years (about 60,182 Earth days).

Rotation Period: Neptune’s rotation period, or length, is about 16 hours and 6 minutes (sidereal).

It has axial tilt about 28.32 degrees relative to its orbit, similar to Earth’s 23.4 degrees, causing seasonal variations over 165-year orbit.

As a fluid gas giant, it shows differential rotation: equator ~18 hours, poles ~12 hours, averaging 16.1 hours measured via cloud features.

Orbit: Neptune’s orbit is nearly circular with a very low eccentricity of 0.0086-0.0113, second only to Venus among planets, resulting in minimal distance variation (perihelion ~29.8 AU, aphelion ~30.3 AU).

The orbital plane inclines 1.77 degree relative to Earth’s ecliptic, a slight tilt causing negligible effects on its path.