This picture shows geysers near Triton's South Pole. The geysers shoot dark material high into Triton's atmosphere. This dark plume settles back down to Triton's surface. Scientists think we can tell which way the wind blows on Triton because of this! Do you see how the geyser plumes point from lower-left towards upper-right in this picture? Can you find any other geyser plumes (besides the two that the arrows point to) in this picture?
Image courtesy NASA/JPL/USGS.