The Pilbara in northwestern Australia exposes some of the oldest rocks on Earth, over 3.6 billion years old. The iron-rich rocks formed before the presence of atmospheric oxygen, and life itself. Found upon these rocks are 3.45 billion-year-old fossil stromatolites, colonies of microbial cyanobacteria. The image is a composite of ASTER bands 4-2-1 displayed in RGB. The image was acquired October 12, 2004, covers an area of 49.1 by 55.2 km, and is located at 22.8 degrees south, 117.6 degrees east. https://photojournal.jpl.nasa.gov/catalog/PIA25122