NEPTUNE
From time to time, Neptune develops relatively short-lived storm systems, which appear as dark-regions. Here the Great Dark Spot of 1989 can be seen, with the Small Dark Spot below it.
Image credit: Voyager 2, NASA.
Neptune Facts
Diameter: 49,528 kilometres (49 thousand, 528 kilometres), or 30,774 miles (30 thousand, 774 miles)
Distance from the Sun: 4,504,450,000 kilometres (4 billion, 504 million, 450 thousand kilometres), or 2,798,900,000 miles (2 billion, 798 million, 900 thousand miles)
Rotation period (day): 16.1 hours
Orbital period (year): 164.79 years or 60,182 Earth days or 89,666 Neptunian days
Cloud-top temperature: -218 degrees Celsius, or -360 degrees Fahrenheit
Moons: 14 in total, namely, Naiad, Thalassa, Despina, Galatea, Larissa, S/2004 N 1, Proteus, Triton, Nereid, Halimede, Sao, Laomedeia, Psamathe and Neso
High wispy clouds cast shadows on the lower cloud deck.
Image credit: Voyager 2, NASA