▸ A lonely instrument in Baja California records tiny fluctuations in the Earth's magnetic field, giving valuable information on the location of geothermal energy.

▸ An extremely quiet amplifier detects electrical noise generated by the fluctuating spins in a collection of chlorine nuclei—the first observation of nuclear‐spin noise.

▸ Superconducting gradiometers in liquid helium measure tiny fluctuating magnetic fields emanating from the human brain (see figure 1), pinpointing the source of the electrical discharge associated with focal epilepsy.

▸ An aluminum bar weighing 4800 kg and cooled to 4.2 K rests in a vacuum chamber at Stanford University, working as the world's most sensitive monitor of gravitational radiation.

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