converted PNM file

This composite image—created from a mosaic of images of the moon Triton, which was then composited against an image of Neptune—shows how Neptune might look as seen from behind the largest of its thirteen moons. Triton’s eroded south polar cap, the result of prolonged Sun exposure, is shown in detail, as is Triton’s surface, which has a number of craters as well as smooth volcanic plains and icy lava flows. Its crust, made of frozen nitrogen, is believed to cover a dense core of rock and metal. Triton is the only large moon that we know of with a retrograde orbit (meaning it orbits in a direction counter to Neptune’s rotation). Scientists believe that Triton is a Kuiper Belt object that was pulled in by Neptune’s gravity millions of years ago. Like our Moon, Triton is in a synchronous rotation with its mother planet, meaning that only one side of the moon ever faces the planet.
Image credit: NASA, JPL-Caltech, SSI
The Planets: Photographs from the Archives of NASA text by Nirmala Nataraj, photographs by NASA, preface by Bill Nye (Chronicle Books, £30)

« Previous Image | Full-Size Image |  Main Gallery Page | Next Image »

converted PNM file

Leave a Reply