This image of Neptune's satellite 1989N1 was obtained on Aug. 25, 1989 from a range of 146,000 kilometers (91,000 miles). The resolution is about 2.7 kilometers (1.7 miles) per line pair. The satellite, seen here about half illuminated, has an average radius of some 200 kilometers (120 miles). It is dark (albedo 6 percent) and spectrally grey. Hints of crater-like forms and groove-like lineations can be discerned. The apparent graininess of the image is caused by the short exposure necessary to avoid significant smear. The Voyager Mission is conducted by JPL for NASA's Office of Space Science and Applications.
NASA/JPL
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