What does this number measure?
A reference for the region of the giant planets. Neptune follows an orbit about thirty astronomical units from the Sun. This reference compares an approximate orbital diameter, about twice that distance.
Compare the stated dimensions
The comparison uses the number in each fact sheet: altitude, height, diameter, length or distance, depending on the reference. Two values in metres do not necessarily describe the same property.
Source and limitations
Catalogue order of magnitude; a source is provided, but this measurement has not been individually audited.
Neptune's orbit: vector diagram of the horizontal reference diameter. The projection of the plane is simplified; the small dot and the Sun are symbolic markers shown out of scale. No position for a particular date or other planet is depicted.