The sound that rang out through the developing universe in the millennia after the Big Bang didn’t sound like an echo, but more like a deep, transfixing hum of decelerating oscillations. In fact, it was so deep that the frequency would have to be boosted 100 septillion times to be heard by human ears.

Ten years ago, a science fair question from an 11-year-old prompted John Cramer, a UW physics professor, to create a simulation of this sound using Cosmic Microwave Background (CMB) radiation recorded by NASA's Wilkinson Microwave Anisotropy Probe (WMAP). This radiation is a ghostly imprint left behind by the original “recording” of the sound, which was a series of compressed and rarefied stretches of matter shaped by the sound wave as it travelled through the universe. The compressed areas were hotter, and the rarefied ones cooler, creating a heat map.

Cramer used new, much higher resolution CMB data released by ESA’s Planck space telescope, to create an updated recording over the weekend. The sped-up recording simulates the sound from 380,000 years to 760,000 years after the big bang.

Cramer is currently exploring nonlocal quantum communication at UW, is a Science Columnist at Analog Magazine and writes hard science fiction.