"Now, most astronomers hate dust; dust can dim the light from background stars and galaxies that we're trying to observe. But I love dust. Stellar nurseries are dusty. And we can use our knowledge of dust to understand the structure of molecular clouds. Stellar nurseries are threaded by these long, dense noodlelike structures called filaments. Embedded within filaments are these compact knots of gas called cores — the final stage before star formation."