In a spacious room with towering ceilings, a gleaming device resembling a metal barrel the size of an SUV lies on its side, ready to perform some science.

Known as the Facility for Laboratory Reconnection Experiments (FLARE), the machine represents the next generation of research into fundamental plasma physics at the U.S. Department of Energy's (DOE) Princeton Plasma Physics Laboratory (PPPL). At 12 feet long, 9 feet in diameter and weighing more than 10 tons, FLARE is a first-of-a-kind, world-class facility.

On June 12, the Laboratory celebrated the beginning of operations for FLARE with a private ribbon-cutting event. More than 50 people gathered for the invitation-only affair, including officials from DOE, Princeton University and PPPL.

"This is the day when we deliver FLARE to the world," said PPPL Director Steve Cowley. "We have fulfilled our promise to design and build this one-of-a-kind device and offer it to the scientific community. I expect FLARE to produce important insights for plasma science in the coming years, and I just can't wait."

FLARE allows researchers to study magnetic reconnection, a phenomenon that occurs when magnetic field lines snap apart and join together again, releasing enormous amounts of energy. Reconnection occurs throughout the universe and powers giant plasma eruptions on the sun's surface known as solar flares.

These eruptions can generate strong winds of electrically charged particles that stream into the solar system. They can also strike Earth's outer atmosphere, damaging communications satellites, global positioning systems and electrical grids, potentially leading to blackouts and internet outages. Moreover, reconnection occurs inside doughnut-shaped fusion devices known as tokamaks, disrupting the crucial fusion reactions and interfering with operations.

Until now, scientists have only observed reconnection happening at one location, known as an X point, along the boundary when two magnetic field lines meet. FLARE will answer the question of whether reconnection can occur at multiple X points simultaneously by replicating more closely conditions as they actually occur in outer space. FLARE will also help scientists understand more thoroughly how reconnection heats the plasma around it, including exactly how much energy goes into heating and how fast that heating occurs. By demonstrating multi-X-point reconnection, scientists will broaden their understanding of reconnection as it occurs in nature.

"That's FLARE's mission goal," said Jongsoo Yoo, deputy head of discovery plasma science, a PPPL principal research physicist and a member of the FLARE team. "We believe that in large astrophysical systems, reconnection occurs at a large number of locations at once, but because of limitations in research space and available energy, we haven't been able to conduct experiments to observe what happens. So far, there hasn't been any hard evidence either way. We're going to change that. We believe FLARE will be the first device to show experimentally that reconnection can occur at many X points."

But how can a large metal barrel mimic huge expanses measuring light years across? The answer depends on comparison - how the size of the reconnection events compares to the overall size of the space inside FLARE. By squashing the circular motion of charged particles such as electrons around magnetic field lines, FLARE's magnets shrink the size of a current of electricity flowing through the plasma. And because reconnection depends on the properties of electrical currents, the reconnection sites in FLARE are relatively small.

That shrinkage matters because scientists want to create reconnection sites that are small compared to the empty space around them, just as in outer space. This technique resembles what engineers would do if they wanted to learn whether an airplane can fly safely in a thunderstorm. They could either fly a real airplane in a storm or put a foot-long model in a wind tunnel. FLARE represents the second approach.

FLARE's prodigious power

FLARE's capabilities allow it to gather information that even spacecraft cannot provide. Because FLARE is in a laboratory, scientists can use probes to measure the reconnection events directly. In addition, spacecraft missions intended to study reconnection in space, like NASA's Magnetospheric Multiscale Mission, involve a limited number of spacecraft, meaning that scientists can measure only a very small section of space. In contrast, FLARE allows scientists to take as many measurements as they want and get a more comprehensive picture of what's occurring.

FLARE also beats high-powered computer simulations in terms of accuracy. "Simulations aren't real," said Ji. "Instead, they are trying to be real. They incorporate a lot of approximations, but because there are so many, lots of important physics is lost. And we don't know whether the lost physics is important." Just as the recording of your favorite song in a lossless compression file has more information than a typical MP3 audio file does and leads to a richer listening experience, experiments conducted using FLARE will provide a more nuanced and complete understanding of reconnection.

In short, scientists will use FLARE to explore the universe without leaving the lab. "There is no way we can reproduce the full range of astrophysical conditions under which magnetic reconnection occurs without creating another universe," Ji said. "But the beauty of physics is that you don't have to."

An international hub of scientific discovery

The opening of FLARE is a significant step toward understanding the complicated physics happening in outer space, on the surface of stars and in devices built to study and harness fusion energy. "FLARE matters to PPPL and the world because it's important for both astrophysical and fusion plasma studies," Ji said. "This next-generation machine confirms that we are both a national and international leader in this research."

Related Links
Facility for Laboratory Reconnection Experiments (FLARE)
Understanding Time and Space