Since the days of NASA’s Apollo program, astronauts have documented (and contended with) how liquids behave differently in microgravity than they do on Earth – coalescing into floating spheres instead of bottom-heavy droplets. Now, researchers have demonstrated this effect with a much more exotic material: gas cooled to nearly absolute zero (minus 459 degrees Fahrenheit, or minus 273 degrees Celsius), the lowest temperature matter can reach.

Using NASA’s Cold Atom Lab, the first-ever quantum physics facility aboard the International Space Station, researchers took samples of atoms cooled to within a millionth of a degree above absolute zero and shaped them into extremely thin, hollow spheres. The cold gas starts out in a small, round blob, like an egg yolk, and is sculpted into something more like a thin eggshell. On Earth, similar attempts fall flat: The atoms pool downward, forming something closer in shape to a contact lens than a bubble.

In this image, inside NASA’s Cold Atom Lab, scientists form bubbles from ultracold gas, shown in pink in this illustration. Lasers, also depicted, are used to cool the atoms, while an atom chip, illustrated in gray, generates magnetic fields to manipulate their shape, in combination with radio waves.

Learn more: Ultracold Bubbles on Space Station Open New Paths for Quantum Research

Image Credit: NASA/JPL-Caltech






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