Five states of matter exist. Most people learn about four states of matter: solid, liquid, gas, and plasma. The fifth is rarer, stranger, and until recently visible only in tightly controlled laboratory environments on Earth. Aboard the International Space Station, NASA’s Cold Atom Lab has been producing this fifth state - Bose-Einstein condensates - since 2018. In May 2026, an upgrade changed what the lab can do with them. The results became available to researchers on 16 June.
The Cold Atom Lab space upgrade is the fourth hardware revision the instrument has received since arriving on the station eight years ago. The new SM-3X science module and HXM-1 electronics module were delivered to the ISS on the NG-24 mission in April 2026 and installed by astronaut Jessica Meir. Together they allow the lab to produce Bose-Einstein condensates five times larger than its previous maximum - and to shape them in three dimensions using a new magnetic trap that earlier versions of the hardware could not provide.
A Bose-Einstein condensate (BEC) forms when atoms are cooled to temperatures just above absolute zero: -273.15 °C, or, as the instrument’s operating parameters frame it, below -459 °F. At those temperatures, the thermal motion that ordinarily keeps atoms behaving as distinct particles becomes negligible. The atoms lose their individual identities. They form a single coherent quantum object in which the wavelike nature of matter - described by quantum mechanics and quantified by the de Broglie wavelength - dominates over particle-like behaviour. The result is a cloud of matter that behaves less like a gas and more like a single, extended quantum wave.
Cold atom experiments have been performed on Earth for decades. The problem with running them at ground level is gravity. On Earth, a BEC cloud in a magnetic trap falls under its own weight within milliseconds, limiting the time available to observe and manipulate it. Gravity also places a floor on how cold the atoms can practically get - because even a very gentle magnetic trap must work harder to hold atoms in place against gravitational pull, and working harder means introducing perturbations that add energy to the system.
In microgravity aboard the ISS, both constraints disappear. Atom clouds can be observed for seconds rather than milliseconds. The trapping fields can be reduced to almost nothing, allowing temperatures that are simply inaccessible on the ground. This is why the Cold Atom Lab space upgrade is scientifically significant in ways that go beyond the hardware specifications.
Jason Williams, project scientist at NASA’s Jet Propulsion Laboratory (JPL), described the upgraded lab as enabling the study of matter in conditions where “the wavelike nature of matter dominates, and ultracold matter can behave in ways that are not only unexpected but potentially useful.” The new magnetic trap’s ability to sculpt gas clouds into different three-dimensional shapes - spheres, rings, sheets - means researchers can engineer specific quantum geometries to probe different physical phenomena. No earlier version of the Cold Atom Lab could do this.
Ethan Elliott, the lab’s deputy project scientist, characterised the work as “quantum 2.0 - direct manipulation of large quantum states.” The phrase captures what has shifted: earlier cold-atom experiments were largely observational. The upgraded system is about deliberate control. Kamal Oudrhiri, the project manager, put it plainly: “It’s the closest thing we have to controlling the boundary of the quantum world.”
The lab is roughly the size of a minifridge and operates remotely from Earth. Five international research teams currently use it, directing experiments from their home institutions while the hardware runs autonomously on the station. This is the final hardware upgrade planned before the ISS retires around 2030. What the lab produces between now and then will inform the design of future quantum instruments - including quantum sensors for precision navigation and gravity mapping of the Earth’s surface and the Moon.
Engineering Deep Dive: Cold Atoms, Quantum Waves, and the Physics of Absolute Zero
The Cold Atom Lab space upgrade sits at the intersection of three areas of A-level physics: states of matter, wave-particle duality, and the behaviour of gases at extreme temperatures. Understanding what the lab actually does requires working through each of these.
Temperature, at the microscopic level, is a measure of the average kinetic energy of particles. In a gas at room temperature, atoms move at hundreds of metres per second, colliding constantly and following classical mechanics. As the temperature drops, average speeds fall. At absolute zero - 0 K, or -273.15 °C, all thermal motion would theoretically cease. In practice, quantum mechanics prevents this: the Heisenberg uncertainty principle means a particle cannot have both a precisely defined position and precisely zero momentum simultaneously. But temperatures can get very close to absolute zero, and at those extremes, quantum effects that are negligible at room temperature become the dominant physics.
The de Broglie wavelength describes the quantum wave associated with any moving particle. The formula is λ = h/mv, where h is Planck’s constant, m is the particle’s mass, and v is its speed. At room temperature, the de Broglie wavelengths of atoms are far smaller than the distances between them. Each atom behaves as an independent particle, and the wave nature of matter is irrelevant. As the temperature falls and the speed v decreases, λ increases. When the de Broglie wavelength becomes comparable to the spacing between atoms, the wave functions of neighbouring atoms begin to overlap. Below a critical temperature, they overlap so completely that the atoms merge into a single coherent quantum state: the Bose-Einstein condensate.
This phenomenon was predicted by Satyendra Nath Bose and Albert Einstein in 1924 and 1925, but not observed in the laboratory until 1995, when Eric Cornell and Carl Wieman at JILA in Colorado cooled rubidium atoms to 170 nanokelvin (billionths of a degree above absolute zero) and confirmed the effect. They shared the 2001 Nobel Prize in Physics for the work.
The Cold Atom Lab uses laser cooling followed by magnetic trapping to achieve its low temperatures. In laser cooling, precisely tuned laser beams are directed at atoms from multiple directions. Photons carry momentum, and when an atom absorbs a photon travelling in the opposite direction to its motion, it slows down. Repeat this millions of times per second, and the atom loses kinetic energy - it cools. Doppler cooling, as this technique is called, can bring atoms to microkelvin temperatures (millionths of a degree above absolute zero). The subsequent magnetic trap further cools the coldest atoms, using the magnetic field to evaporate the most energetic atoms from the cloud and allow the remainder to reach nanokelvin temperatures.
In microgravity, the magnetic trap can be made extremely weak - the atoms no longer need to be held up against gravity. A weaker trap means fewer perturbations, which means lower achievable temperatures and longer coherence times. This is the engineering advantage of conducting the Cold Atom Lab space upgrade aboard the ISS rather than on the ground.
The practical applications being explored include quantum gravimeters - instruments that measure tiny variations in the Earth’s gravitational field by tracking how a BEC responds to gravity. Because quantum measurements can be made with extraordinary precision, these sensors could detect underground cavities, changes in groundwater levels, or even the gravitational signature of dense ore bodies from space. Similar instruments are proposed for the Moon, where mapping the gravitational field with high precision would help locate underground lava tubes that might serve as natural shelters for future explorers.
Quantum inertial navigation is another application. Conventional inertial navigation systems use accelerometers and gyroscopes that drift over time. Cold atom accelerometers measure inertial forces by tracking the quantum phase of atom waves - a measurement that is fundamentally stable and does not accumulate drift errors. This would be valuable for submarines, aircraft, and spacecraft operating where GPS signals are unavailable.
The Cold Atom Lab space upgrade is, in this sense, both a physics experiment and an engineering prototype programme. The science answers fundamental questions about quantum matter. Engineering develops techniques that will eventually make quantum sensing instruments robust enough to leave the laboratory and operate in the field.
The BECs produced by the upgraded Cold Atom Lab are five times larger than before and can be sculpted into shapes no previous version of the instrument could form. What researchers do with that capability over the next four years - before the ISS comes down - will determine how much progress on quantum sensing and quantum physics actually transfers from orbit to the world below.
- NASA’s fourth Cold Atom Lab space upgrade, installed in May 2026 by astronaut Jessica Meir, became operational on 16 June and produces Bose-Einstein condensates five times larger than before.
- Bose-Einstein condensates are a fifth state of matter where atoms are cooled to just above absolute zero and behave collectively as quantum wave objects.
- The new magnetic trap can reshape quantum gas clouds into different three-dimensional geometries — a capability no previous version of the lab possessed.
- Microgravity on the ISS allows longer observation times and lower temperatures than any Earth-based cold atom experiment.
- This is the final planned hardware upgrade before the ISS retires around 2030, supporting five international research teams.
