In an otherwise unassuming facility in northern Seattle, a supercooled tangle of tubes and wires is poised to remake the world. Coursing with liquid helium, the device's interior hovers less than a tenth of a degree above absolute zero, the coldest possible temperature. Inside the frigid cavity, carefully shielded from noise, microwave radiation can resonate like sound waves in a bell, hunting for hints of particles whizzing through that, in all other contexts, would be invisible.
Meet the Axion Dark Matter eXperiment, or ADMX: the most sensitive scientific instrument of its kind ever built. If ADMX confirms the existence of its prey, a theoretical particle called the axion, it could finally explain the massive cosmic mystery of dark matter.