Photograph of one of Neptunes moons, known as 1989N1, taken as the spacecraft approached Neptune on 25 August, 1989. The moon, seen here half- illumin

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Photograph of one of Neptunes moons, known as 1989N1, taken as the spacecraft approached Neptune on 25 August, 1989. The moon, seen here half- illuminated, has an average radius of some 200 km. It is dark grey in colour and hints of crater-like forms and linear grooves can be discerned. The graininess of the image is caused by the short exposure necessary to photograph the speeding moon. The photograph was taken from a distance of 146,000 km and has a surface resolution of about km.

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Size: 3401px × 4657px
Photo credit: © NASA/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: 1989n1, astronomy, cosmology, neptune, planet, planetary, science