Icy Moons


On August 25, 1989, Voyager passed within 40,000 kilometers of Neptune's large moon Triton, the last such visit the pioneering Voyager Project would make as it exited the then-known Solar System. In commemoration of the 25th anniversary of this event, a new high-resolution global map in 3-colors has been made of Triton, highlighting the young geologically active surface of the cold icy moon. The map is also in support of the New Horizons Pluto encounter in July, 2015.

The map has a nominal resolution of 600 meters and is in orange, green and blue, showing Triton in approximately natural colors. The dark areas to the north were not illuminated during the Voyager encounter. The map is centered on the Equator and extends to 180° W (at left) and 180° E (at right), and from North (top) to South poles (bottom).

Dr. Schenk’s blog entry about the Neptune-Triton encounter, the Pluto encounter in 2015, and the new Triton Map.

Image Advisory  

Credits citation for public use of maps:

Image selection, radiometric calibration, geographic registration and photometric correction, and final mosaic assembly were performed by Dr. Paul Schenk at the Lunar and Planetary Institute, Houston, Texas. Image data from Voyager 2 (NASA, JPL).

The global map is in two formats: a full resolution jpeg, and an annotated jpeg with ancillary information suitable for poster-sized printers and wall mounting. A polar orthographic version of the poster is also available.

Global Mosiac
Triton - global mosaic

  Download a hi-res version of the image

Annotated Global Map Poster
Triton - Annotated Global Map Poster

  Download a hi-res version of the image

Polar View Poster
Triton - Polar View Poster

  Download a hi-res version of the image

Triton Movie

Voyager 2 made a hair-raising pass over Neptune’s large moon Triton in August 1989. Approaching from the deep south, Voyager passed over the north pole of cloud-swept Neptune, almost close enough to brush the far-attenuated upper atmosphere.The gravity of Neptune pulled the spacecraft down toward Triton, passing over the unlit north pole of that bitterly cold icy moon.This movie, using the best Voyager map, in color, recreates that encounter with Triton as Voyager 2 ended its tour of the Giant Planets and began its lonely trek into deep space.Triton is 2706 kilometers across.The map has a nominal resolution of 600 meters and is in orange, green and blue, showing Triton in approximately natural colors.The actual encounter as represented here begins about 3 days out from Triton (extending a week on the outbound trajectory) and at a speed of ~25 kilometers per second.

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