When you look at distant galaxies through a telescope, you're looking back in time as well as space because it takes light so long to travel that far. So when Yale astronomer Pascal Oesch and his team looked through some of the most powerful and advanced telescopes ever built they were looking back 13 billion years, almost all the way back to the Big Bang.
"These telescopes are like a time machine," Oesch says. "And you are able to look back in cosmic history to a time when the universe was still very young, so these galaxies were very small, like infants. And we're trying to understand how they were growing."
Last week Oesch and his team found the oldest galaxy mankind has ever seen from earth. It's called EGS-zs8. Maybe the name's not as catchy as the Milky Way, but in the early days of the universe, EGS-zs8 would have been one of the brightest things in the sky, giving birth to new stars at a furious pace. Oesch says in the future, it's going to help astronomers answer some big questions.
"Where did everything that we see around us in the universe actually come from?" he says. "You know, what are our cosmic origins? When and how did the heavy elements form in the universe? And these elements are ones that make up all of us, that make up earth. That process started with the formation of the first stars and the first galaxies more than 13 billion years ago."
Oesch says as telescope technology advances, astronomers will be able to study this galaxy more closely, and to see even further back into the history of the universe. They know there are galaxies even more distant out there. Oesch's team is only one of several trying to find them.
