Seth Patterman started For national security reasons, we have not studied plasma behavior. Extremely fast hypersonic missiles heat and ionize the air around them, forming clouds of charged particles called plasma. Plasma absorbs radio waves, making it difficult for ground operators to communicate with the missile. That’s the problem Patterman was trying to solve. Then he had an idea: the same plasma physics apply to our Sun.
A UCLA scientist and his colleagues have now created what Putterman calls “our sun in a jar.” This is a 1.2 inch glass sphere filled with plasma and used to model processes such as those that produce solar flares. These are explosive bursts of energy that can be accompanied by the release of high-velocity clumps of plasma that can wreak havoc on satellites in orbit and power grids on the ground. “The steps we are taking will impact modeling to enable space weather precursor warnings and decisions,” says Patterman, senior author of the study. physical review letter describe their experiments.
The sun is basically a swirling hell of plasma made up of rotating, electrically charged gas particles, most of which are electrons and hydrogen atoms with their electrons removed. (Stellar plasma is a bit different than the low-density plasma used in tokamak fusion reactors.) Researchers are trying to better understand solar flares, especially when large plasma clumps are fired toward Earth. I have searched for a long time.
The team’s experiment involves placing partially ionized sulfur gas inside a glass sphere and irradiating it with low-frequency microwaves, similar to the kind used in microwave ovens, to excite the gas and heat it to about 5,000 degrees Fahrenheit. started by doing They found that his 30 kHz pulses of microwaves set up sound waves that exert pressure on hot gases to contract. This sonic pressure creates a kind of ‘acoustic gravity’ that causes fluids to move as if they were in the Sun’s spherical gravitational field. (The experimental gravitational field is about 1,000 times stronger than Earth’s.) This creates plasma convection. In this process, a warm fluid rises and a cooler, denser fluid sinks into the core of the glass sphere. The team thus became the first people on Earth to create something akin to the spherical convection currents normally found inside stars.
Their project was originally funded by DARPA, the Advanced Research Division of the Department of Defense, for hypersonic applications. It then gained the backing of the Air Force Research Laboratory because space weather can interfere with aircraft and spacecraft. But astronomers also think they can tell us something fundamental about the behavior of the Sun. “I think the real significance is to start simulating solar convection in the lab and gain insight into the sun’s mysterious solar cycle,” said the university’s Center for Space Weather Technology, Research, and Education. Executive His Director Tom Berger said. The Boulder Colorado study was not involved.
Berger describes a cycle of about 11 years in which the Sun’s internal convective zone somehow becomes more active, leading the outer layer or corona to produce more frequent and powerful flares and explosions of plasma called coronal mass ejections. I am referring to NASA has a difficult time examining the sun’s inner regions with a spacecraft called the Solar Dynamics Observatory, which uses sound waves to map the sun’s surface and make inferences about the plasma beneath it, Berger said.
Others in the field also praise Patterman and his colleagues’ work, but point to its limitations. “This is an exciting and innovative development. It’s well done. Simulating the internal dynamics of stars in the lab has always been a challenge,” said researchers at the NOAA Space Weather Center and the University of Colorado. says Mark Miesch.
