The Universe's Dark Ages

ESA's Herschel space telescope has discovered that previously unseen distant galaxies are responsible for a cosmic fog of infrared radiation. The galaxies are some of the faintest and furthest objects seen by Herschel, and open a new window on the birth of stars in the early universe. To date, it is the most sensitive image of the universe taken with Herschel. CREDIT: ESA/PEP Consortium  View full size image

The dark ages of the universe — an era of darkness that existed before the first stars and galaxies — mostly remain a mystery because there is so little of it to see, but scientists intensely desire to shed light on them in order to learn secrets about how the universe came into being.

"The dark ages represent our origins — when the very first stars formed and created the heavy elements we are made of today," said theoretical astrophysicist Abraham Loeb, chairman of the astronomy department at Harvard University.

Now researchers are developing tools for gazing back into this hitherto enigmatic time. To put things in perspective, astronomers estimate that the universe is 13.7 billion years old.