Like his father, Robert John Strutt was also a physicist. In fact, he has followed up his father's work on light scattering, which is now known as Rayleigh scattering, resulting in some papers published in the Proceedings of the Royal Society. He published a biography of his father, the third Baron Rayleigh, with the title of "Life of John William Strutt, third Baron Rayleigh". Photographs of Robert John Strutt when he was young can be found in this book. Both the father and son's work on light scattering was discussed by Young in 1982. A sketch of Robert John Strutt when he was old can also be found in Young (1982). (Please see reference.) Both the rayleigh, a unit of luminous flux used to measure air glow, and the rayl, a unit of acoustic impedance, are named after Robert John Strutt.