The "XDF" image was released on September 25, 2012. The image combined 10 years of images. It shows galaxies that are over 13.2 billion years old. The exposure time was two million seconds, or about 23 days. The least bright galaxies are one ten-billionth the brightness of what the human eye can see. Many of the smaller galaxies are very young galaxies. Some of them became the major galaxies, like the Milky Way and other galaxies in our galactic neighborhood. 