Even a celestial body as familiar as the sun has a few secrets. Above the sun’s visible surface, hot gases made up of charged particles stretch into space to form the sun’s superheated outer layers, including the streaky corona, which can be seen looking like a lion’s mane during a total solar eclipse. Some process heats up these plasmas in the corona to millions of degrees and makes them speed away from the sun as solar wind.

Exactly how these plasmas escape the sun’s magnetic fields is still a mystery. “A lot of the open questions about the sun eventually come down to the magnetic field” because magnetic fields govern much of the sun’s activity, said Therese Kucera, an astrophysicist at NASA’s Goddard Space Flight Center who studies the sun’s atmosphere.

The sun’s magnetic fields form enormous loops that extend from the sun’s surface into space. Some of these loops are small enough to fit entirely within the sun’s corona, while others stretch to the edges of the solar system.

In general, these loops trap plasmas because charged particles travel along magnetic fields rather than across them. Some plasmas escape from the sun by following the loops that extend far into the solar system. These plasmas become the so-called “fast” solar wind. Scientists think that blobs of plasma can also break out of the smaller loops to generate the “slow” solar wind. The loops break and reattach themselves in a process called reconnection, sloughing off some of the trapped plasma. But the details of where and how magnetic reconnection happens have eluded us.

“We want to do more than just wave our hands and say, ‘Oh, it must be related to reconnection somehow,’” Kucera said.

So a team of researchers decided to try to re-create the sun’s magnetic field structure in a ball of plasma in their laboratory.