Space is a continuous symphony of melodies, even though, unfortunately, we cannot hear them from Earth. For a couple of decades, however, space telescopes have allowed us to hear for the first time the unique songs emanating from the hearts of stars, which tell us what has so far been invisible to science and human knowledge: the inner life of these celestial bodies, fundamental building blocks of galaxies and the Universe, and true factories of the materials we are made of. As astrophysicist and science communicator Carl Sagan said, "we are all stardust."