Galaxies turn gas into stars. In order for the gas to end up as a star it needs to cool down during the process, this means that at some point the gas must be neutral and cold. Using carbon as a tracer of the cold gas (carbon is the 3rd or 4th most abundant element in our Galaxy, depending on the region) we aim to understand the properties of this cold gas. Once we know its properties we can judge if the gas will continue cooling and end up forming molecular gas clouds, the birth site of stars, or if it will heat up and become unstable.
As part of my MSc I built a radio interferometer that is now being used to teach the principles of interferometry.