In about six months, another SpaceX Falcon 9 rocket will be on its way to the International Space Station. Besides the usual supplies that keep the ISS stocked, an experiment the size of an ice chest will be tucked inside. It’s called the Cold Atom Laboratory, and it will create the coldest spot in the entire universe.
This sucker puts your cooler to shame. While you’re dragging a cooler full of cold ones around this summer, the Cold Atom Laboratory will be freezing gas atoms to a billionth of a degree above absolute zero. Just shy of minus 459.67 degrees Fahrenheit.
How the Cold Atom Laboratory works
Tucked inside this box is a vacuum chamber, lasers and what NASA describes as an electromagnetic ‘knife.’ Combined, the instruments will slow the gas particles until they are nearly motionless.
The Cold Atom Laboratory.
Wait, lasers? Yep. Most of us see lasers as having to do with heat. Real word applications like laser cutting in manufacturing or medical applications. But lasers can also cool in a technique aptly named laser cooling. That’s what the Cold Atom Laboratory will do.
But how? Cooling atoms is all about slowing them down. Scientists need a way to push on them to get them to almost stop. That’s where lasers come in. Shine a laser at a row of atoms, and they begin to slow, and cool. As they get slower and slower and cooler and cooler, the atoms form a new state of matter called a Bose-Einstein condensate. Here, the normal rules of physics fade to the background and quantum physics starts to take over.
Instead of banging around like particles, or billiard balls, the rows of atoms behaves more like a wave. Instead of this:
Scientists start observing behavior like this:
CAL Project Scientist Robert Thompson explains why studying freezing atoms is important. “Studying these hyper-cold atoms could reshape our understanding of matter and the fundamental nature of gravity,” says Thompson. “The experiments we’ll do with the Cold Atom Lab will give us insight into gravity and dark energy – some of the most pervasive forces in the universe.”
Why does the Cold Atom Laboratory need to be in space?
The always present force of gravity works against scientists here. On Earth, the atoms always want to settle towards the ground, giving scientists just fractions of a second to observe them in their unique state.
But the pull of gravity isn’t as strong on the ISS. Those fractions of a second turn into up to 10 seconds according to Thompson.
The 10 seconds give scientists a brief, but vital window into understanding the physics at play here.
Bose-Einstein condensates are also dubbed a ‘superfluid.’ This is a kind of fluid with zero viscosity (no friction). Anita Sengupta, the project manager for Cold Atom Laboratory, explains:
“If you had superfluid water and spun it around in a glass, it would spin forever. There’s no viscosity to slow it down and dissipate the kinetic energy. If we can better understand the physics of superfluids, we can possibly learn to use those for more efficient transfer of energy.”
Several teams plan to conduct experiments. What they learn over the coming months and years could be put to use in a wide range of applications including sensors and quantum computers. It could also help in our ongoing search for the elusive dark matter.
“Like a new lens in Galileo’s first telescope, the ultra-sensitive cold atoms in the Cold Atom Lab have the potential to unlock many mysteries beyond the frontiers of known physics,” says deputy project manager Kamal Oudrhiri.
Between now and launch, the Cold Atom team will conduct tests to make sure the laboratory is perfectly calibrated to conduct these experiments in space.
It will mark the first time NASA has created or observed Bose-Einstein condensates in space. The team hopes further development of technologies used in the Cold Atom Laboratory can boost that to hundreds of seconds.
Still curious about laser cooling? Here’s a great video from Physics Girl and Veritasium on how it works.