NASA is experimenting with the use of quantum technology to measure gravity, magnetic fields, and other forces in space. The space agency just tested a brand new tool on board the International Space Station (ISS) to measure the vibrations of the orbital lab using ultra-cold atoms.

The quantum tool, called an atom interferometer, uses atoms that are laser-cooled to millionths of a degree above absolute zero to garner precise measurements of the properties of atoms themselves. That’s even colder than space, which exhibits an ambient temperature 2.725 degrees Kelvin above absolute zero.

Although atom interferometers are used on Earth, they were considered too fragile to function for longer periods of time in space. However, using NASA’s Cold Atom Lab—a facility on the ISS about the size of a mini fridge—scientists proved that it’s possible to use atom interferometers in space. The results of the latest experiment is detailed in a recent study published in Nature Communications.

The Cold Atom Lab takes advantage of the microgravity environment on board the ISS to study quantum phenomena. The lab cools atoms to almost absolute zero, or -459 degrees Fahrenheit (-273 degrees Celsius). At those ultra-cold temperatures, the atoms form a fifth state of matter (unlike solid, liquid, gas, or plasma) called a Bose-Einstein Condensate, which makes the quantum properties of atoms macroscopic rather than microscopic. As a result, the atoms’ properties are easier to observe.

In the microgravity environment of the ISS, the state of Bose-Einstein Condensates can last longer and reach colder temperatures, creating an even better opportunity for observations. Using an atom interferometer, scientists take advantage of the wave-like properties of atoms, which can cause a single atom to simultaneously travel two physically separate paths. When the atom’s waves recombine and interact, scientists can measure the influence of gravity or other forces that acted on those waves.

Having a space-based atom interferometer that can measure gravity with extreme precision can help scientists get a better understanding of the composition of moons and other celestial bodies. Different densities and materials of moons and planets result in subtle variations in gravity. Precise measurements of gravity can also give scientists rare insight into dark matter—the most elusive material of the cosmos.

“Atom interferometry could also be used to test Einstein’s theory of general relativity in new ways,” Cass Sackett, a Cold Atom Lab principal investigator and co-author of the new study, said in a statement. “This is the basic theory explaining the large-scale structure of our universe, and we know that there are aspects of the theory that we don’t understand correctly. This technology may help us fill in those gaps and give us a more complete picture of the reality we inhabit.”

NASA’s Cold Atom Lab launched to the ISS in 2018 and was the first to create Bose-Einstein Condensates in orbit. The lab is operated remotely from Earth, and discoveries using the facility could one day help us reach farther into space and better understand our surrounding universe.

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