For the first time scientists have observed the dust contents of galaxies as seen just 1 billion years after the Big Bang.
Dust in galaxies is created by the elements released during the formation and collapse of stars. Although the most abundant elements in the universe—hydrogen and helium—were created by the Big Bang, stars are responsible for making all of the heavier elements in the universe, such as carbon, oxygen, nitrogen, and iron.
And because young, distant galaxies have had less time to make stars, these galaxies should contain less dust. Previous observations had suggested this, but until now nobody could directly measure the dust in these faraway galaxies.
“Before we started this study, we knew that stars formed out of these clouds of gas and dust, and we knew that star formation was probably somehow different in the early universe, where dust is likely less common. But the previous information only really hinted that the properties of the gas and the dust in earlier galaxies were different than in galaxies we see around us today. We wanted to find data that showed that,” says Peter Capak, a staff scientist at the Infrared Processing and Analysis Center (IPAC) at Caltech and the first author of the study in Nature.
