neptune's orbit is 164 years so observations (1950 to present day) span less than a third of a neptunian year.
neptune's orbit is 164 years so observations (1950 to present day) span less than a third of a neptunian year.
neptune:4
neptune orbits the sun once every 164.8 years at an average distance of 30.1 au (4.5 billion km; 2.8 billion mi).