Artist’s impression of a gas cloud.
(Credit: ESO/L.
How do they know this?
Artist’s impression of a gas cloud. (Credit: ESO/L. Calçada, M. Kornmesser)
These giant stars quickly exploded in supernovas and enriched the surrounding gas with heavier elements.
By matching the chemical makeup of a gas cloud, scientists can estimate its age.
In this case, the researchers were looking for gas clouds that lacked heavy elements, like iron.
Diagram illustrating how astronomers can analyze the chemical composition of distant clouds of gas using a quasar as a beacon. (Credit: ESO/L. Calçada)
In these three distant gas clouds, the researchers found just what they were looking for.
(Credit: ESO/L.
Known asquasars, when their light travels through the universe, it travels through the gas clouds.
The chemicals in these clouds imprint onto the light, which can then be studied by scientists.
By using an instrument known as an X-shooter, they can split the light into different wavelengths and colors.
This then allows them to clearly study the chemical composition of the clouds.
With this study, the researchers are paving the way for how to study early star development.
