The sound of thermal radiation
As illustrated for the light curves of periodic variable stars, void of irregular or stochastic variations, they can be described by a set of discrete frequencies, such as fundamental frequencies (perceived as pitch) and their harmonics (perceived as timbre).
Regardless of the variations in a star’s brightness, its luminosity comprises electromagnetic radiation spanning a broad spectrum of frequencies, often extending beyond the limited band perceptible to the human eye. These frequencies exhibit a distinct distribution, which can be approximated by Planck’s law, applicable to thermally radiating objects (with surface temperature greater than absolute zero, i.e., higher than zero kelvin or −273.15 °C or −459.67 °F).
What would such a continuous distribution of frequencies sound like? Too many frequencies (akin to a crowd of people speaking at the same time) are often perceived as a form of noise. Noise can exhibit various ‘colors’ based on its frequency distribution. So, how would the ‘noise’ of thermal radiation sound? Explore the following sound samples, listed in descending order of temperature.
The temperatures mentioned above, which trigger changes in states of matter, are based on a pressure of one atmosphere.
Published: July 27, 2024 | Last Updated: July 31, 2024 | Resources licensed under CC BY 4.0 
