By Jesse Emspak
An enormous explosion, rivaling the most powerful outbursts in the universe, called a supernova, has been created in a lab, along with the associated shock wave of charged particles, scientists report.
The scientists from the University of Oxford weren’t just looking to blow things up. Led by Gianluca Gregori and graduate student Jena Meinecke, the team wanted to know why the magnetic fields in Cassiopeia A, the remains of a star that exploded in a supernova, are intense and uneven in some places, taking on odd shapes. The experiment could also shed light on why magnetic fields in intergalactic space are a million billion times stronger than theory predicts.
Current theories say that the measured fields in interstellar space should be about 10-21 Gauss, with the Gauss being a unit of magnetic field strength. (Earth’s magnetic field varies from 0.25 to 0.65 Gauss, depending on where you are).
The uniformity is because when Earthlings look deep into space, they see the cosmic background radiation, which is a microwave signal that’s an echo of the Big Bang that began the whole universe. That background radiation looks pretty much the same everywhere.
“It’s very smooth, very uniform,” Gregori told Live Science. The smoothness means the space between stars doesn’t produce much electric charge, leading to a very weak — and uniform — magnetic field in that space.
The actual value of that charge is a million billion times stronger than what the theory says it should be. “We have this idea that whatever produced that [background] field has been amplified.”
Blowing up carbon
To help answer the question of why the universe’s magnetic field is so strong, the researchers put a rod of carbon about 500 microns (just under one-50th of an inch) into a chamber filled with argon, an inert gas at low pressure. Near the carbon, they placed a plastic grid, which served as a barrier to simulate the interstellar medium.