In a galaxy far, far away… actually, make that two galaxies! These aren’t just any galaxies, though. They’re in the early universe and are home to some extremely productive star factories. A team of scientists, led by Chalmers University of Technology in Sweden, has been studying these star factories. They used some seriously powerful telescopes to split the galaxies’ light into individual colours. What they found was mind-blowing — light from many different molecules, more than ever before at such distances. This type of research is revolutionary and could change our understanding of the lives of the most active galaxies in the young universe, according to the researchers.
Before you picture stately spirals of galaxies, keep in mind that these early universe galaxies were a whole different ball game. New stars were being born at rates hundreds of times faster than they are in today’s universe, hidden behind thick layers of dust. But thanks to powerful telescopes, astronomers are catching glimpses of how these star factories cranked out so many stars.
Published in the journal Astronomy & Astrophysics, a new study led by Chalmers astronomer Chentao Yang used the telescopes of NOEMA (NOrthern Extended Millimetre Array) in France to dig into how these early star factories created so many stars. And the results? They were out of this world. The team measured light from two luminous galaxies in the early universe — one of them classified as a quasar, and both with high rates of star formation.
“To be able to find out how they work, we measured their light at wavelengths around one millimetre, hoping to collect new clues,” says Chentao Yang.
No one can see it, but deep within these galaxies, light is emitted in many different wavelengths from the clouds of gas and dust where new stars are born. Astronomer Sergio Martín, a member of the research team, describes it as “an amazing explosion of colour.” By combining observations with knowledge of physics and chemistry, they can unlock new insights into these galaxies.
By analyzing the spectrum of each galaxy’s light, the scientists identified 13 molecules, several of which have never been seen before in such distant galaxies. Each molecule provides different clues about the conditions in these galaxies, shedding light on the physical and chemical interactions happening within them.