For decades, astronomers have faced a frustrating puzzle when studying star formation in our Galaxy. They know that most stars are born inside clouds of cold molecular hydrogen gas, but this hydrogen is all but invisible to telescopes because it doesn't emit light that can easily be detected. To find these stellar nurseries, researchers have relied on carbon monoxide as a tracer molecule, find the marker and thats where molecular clouds exist. However, there's been a problem with this approach, substantial amounts of star forming gas simply don't light up in carbon monoxide observations, remaining hidden from view.