It’s a “history book of the universe” according to an astronomer who was as stunned by this image as anybody.
The pinpricks of light in the above image are entire galaxies, not just individual stars. The image is the result of 16 years worth of photos taken by the Hubble Space Telescope, pieced into one single mosaic. There are 265,000 galaxies pictured here.
It’s nearly impossible to imagine, but the mosaic, called the Hubble Legacy Field, is the product of 7,500 individual exposures taken over the years. The faintest images come from 13 billion years ago, only 500 million years after the big bang. Hence the “history book” metaphor.
The patch of space this image was taken from is roughly the size of the moon as seen from earth. Those hundreds of thousands of galaxies are from just a minsiscule sliver of the night sky.
The power of Hubble is one of awe and a sense of exploration. We may not physically reach those stars, but we’re exploring them as best we can. And because of work like this, the universe, and our backyard, continues to expand.