A push at the right moment stops a swing. The delta-kick, a short laser pulse, was applied to a cloud of molecules, and it froze, like a swing after a precise kick. Molecules made of two different atoms, like a seat firmly locked to the swing’s bar, didn't fall apart during deceleration. The temperature dropped to picokelvins — trillionths of a degree above absolute zero, where motion nearly freezes and entropy (a measure of disorder) becomes minimal. Even the internal jitter of atoms didn't disturb the stillness, like a passenger's slight swaying doesn't change the swing's motionlessness. An unexpected fact: at this temperature, the molecular cloud expands slower than grass grows. Now these nearly immobile objects are used to test the law of universal gravitation, which Galileo Galilei tested by dropping cannonballs from a tower, and Albert Einstein linked to spacetime curvature. Based on them, scientists will build spectroscopy, a device capable of detecting even the tiniest deviations.