What's the best way to learn more about the cosmos without ever leaving Earth? A group of scientists from the University of Rochester have the answer to that: lasers.
Using the laboratory at the university's OMEGA EP facility, scientists conducted several experiments. In these experiments, researchers used lasers to mimic solar flares and explosions, creating plasma tsunamis, similar to those that occur in space.
These plasma tsunamis naturally exist at the edges of a supernova, which is a high-energy event when a star explodes, leaving a ball of intensely hot plasma. The star's magnetic field interacts with the plasma, which creates the tsunamis, or shock waves. This happens over and over, and results in cosmic rays.
Researchers recreated this event in the lab with two lasers zapping pieces of plastic in a vacuum chamber. That plastic reached temperatures up to 10 million degrees. This created plumes of hot plasma, similar to that found in space. A third laser sent protons through that plasma.
Researchers witnessed a never-before-seen event. When the plasmas combined, they became filaments. This is the first time scientists have seen this sort of instability. Not only that, but it was completely unexpected. Researchers dubbed this phenomenon as a "Weibel instability."
It is possible that the Weibel instability is what makes the magnetic fields in space that form tsunamis. Those magnetic fields also affect cosmic rays and send them out into space.
Not only could this research help us understand what happens during supernova, but it could also teach us more about magnetic fields and cosmic rays themselves, as well as where plasma comes from.
In a different experiment, researchers used lasers targeted at a sphere. This created huge shock waves, with pressures equal to that of nearly a billion atmospheres. Details from this experiment might further our knowledge of how matter reacts to high densities or in the cores of the gas-giant planets.
This isn't the first time that scientists used lasers to understand the mysteries of the Universe. Earlier this month, researchers created an experiment that might have proved Hawking radiation. This radiation, as theorized by Stephen Hawking, is the energy radiated by black holes.
In this experiment, scientists created a state of matter called the Bose-Einstein condensate, which exists at near absolute zero temperature. Researchers then aimed a laser beam at the condensate, creating an event horizon, which is basically the point of no return inside a black hole where nothing can escape. In the experiment, though, some light from the laser does escape, which researchers suggest represents Hawking radiation.
