This tiny, fuzzy image is of the moon Neried and is typical of most Neptunian moons. More information on the moons can be found on the Neptunian Satellite Fact Sheet.

The exception is Triton. This is the only significant moon of Neptune, and it is believed to be a captured body, forming independently from Neptune. Evidence of this is:

• Retrograde rotation - a signature for a captured satellite
• The orbit is inclined by 23º - most satellites have an orbit at or similar to the orbit of the planet

The image below shows the full face of Triton:

What surprised Astronomers is the appearance of Triton. In this close-up image, we see two features: one distinct, one subtle:

Notice first the cantaloupe appearance. It is thought that there is still some warmth underneath resulting in some resurfacing. The rough appearance are not the result of impacts. Additionally, the black areas on the lower half are believed to be miniature geysers spewing material. The swept-back appearance is evidence that a tenuous atmosphere exists.

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