Color-composite of Triton made from Voyager 2 images acquired on August 25, 1989. Approximate natural color. (NASA / JPL-Caltech / Jason Major)
(News from NASA)
Voyager 2 is the only spacecraft ever to have flown past Neptune, and it left a lot of unanswered questions. The views were as stunning as they were puzzling, revealing massive, dark plumes of icy material spraying out from Triton‘s surface. But how? Images showed that the icy landscape was young and had been resurfaced over and over with fresh material. But what material, and from where? How could an ancient moon six times farther from the Sun than Jupiter still be active?
A new mission competing for selection under NASA’s Discovery Program aims to untangle these mysteries.
Close-up image of Triton’s surface from Voyager 2’s flyby
Called Trident—like the three-pronged spear carried by the Roman sea god Neptune—the team is one of four that is developing concept studies for new missions. Up to two will be selected by summer 2021 to become a full-fledged mission and, if Trident is selected, it would launch in October 2025 (with a backup in October 2026).
The oddities of Triton could fill an almanac: As Neptune rotates, Triton ...