You're listening to NASA's Curious Universe. I'm your host, Jacob Pinter. Out in the cosmos, in the space between stars, gas, dust, and ice mingle in dark clouds.

Eventually, after millions of years, these clouds will evolve into stars, with planets orbiting them.

With telescopes, we can see how it all happens.

And in a lab in the Netherlands, you can almost put your hands on it.

I always like to say that, you know, this is one cubic centimeter of interstellar space

or something like that that we have in the lab.

Evina van Dysuk is an astronomer based at the University of Leiden in the Netherlands.

To figure out how those dark clouds become stars, she combines telescope data with what she sees

in the laboratory.

Your experiments in the lab on Earth will take hours, which is good because then a student

can finish it in a day. Whereas in space space they would take hundreds of thousands of years.

On Earth, you can't manage a perfect simulation of space.

But in some ways, you can get close.

Those clouds of dust and gas are far colder than anything that happens naturally on Earth. They can be below minus 400 degrees Fahrenheit, not far from absolute zero.

Reaching those temperatures is actually not the hard part.

We can't achieve the emptiness of space.

And even the best ultra-high vacuum that we can make in a laboratory on Earth is still a million

times more dense than what we have in space. So when an astronomer talks about a dense dark cloud,

it's still much more empty than anything we have in a laboratory here on Earth.

In the lab, you get a close-up view of the same chemicals we find out in space.

And that helps us understand how they behave and how we can detect them.

Scientists study these clouds and their chemistry in a number of ways,

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