(August 25, 1989) Voyager 2 was the first spacecraft to observe the planet Neptune and its two satellites: Triton, the largest, and Nereid. The most obvious feature of the planet is its blue color, the result of methane in the atmosphere. Research continues on Neptune's two largest satellites and the additional six that were discovered by Voyager 2's investigation. These images represent the most complete set of full disk Neptune images that the spacecraft will acquire.
nasaimages.org/luna/servlet/detail/nasaNAS~9~9~60684~164531#
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