If NASA says it is a magnetic universe then how is the universe magnetized?
The bold title by the University of Chicago is Astrophysicists settle century-old cosmic debate on magnetism of planets and stars. The research paper does not quite take that tone, suggesting it is a viable mechanic.
Laser experiments verify ‘turbulent dynamo’ theory of how cosmic magnetic fields are created ... to demonstrate for the first time in the laboratory the existence of turbulent dynamo, an astrophysical process that has long been theorized to explain the present-day magnetization of the Universe.
Advanced monoenergetic proton radiography, developed by MIT to probe the evolution and structure of fields and plasma flows in high-energy-density-plasma experiments, was used for measuring the spatial structure and temporal evolution of spontaneous magnetic fields which grew, due to plasma turbulence, from an initial value ~ 50 kG to ~ 500 kG. These field measurements, led by MIT senior research scientist Dr. Chikang Li, provided critical experimental evidence of the 10-fold turbulent amplification of the fields. Though the mechanism of field amplification is widely believed to be pervasive in generating strong cosmic magnetic fields, these experimental results are the first laboratory demonstration that many-fold field amplification can result from such plasma turbulence.
Measuring the magnetized universe | Massachusetts Institute of Technology
What, in total, monstrous energetic processes create the magnetization of stars, solar systems, plasma Universe? Gravity? Plasma turbulent dynamos?
Are plasmas responsible for space magnetism?
"We now know for sure that turbulent dynamo exists, and that it's one of the mechanisms that can actually explain magnetization of the universe," said Petros Tzeferacos, research assistant professor of astronomy and astrophysics and associate director of the Flash Center. "This is something that we hoped we knew, but now we do."
The universe is highly magnetic, with everything from stars to planets to galaxies producing their own magnetic fields. Astrophysicists have long puzzled over these surprisingly strong and long-lived fields, with theories and simulations seeking a mechanism that explains their generation. The image shows the magnetic field of the Whirlpool Galaxy, M51.
Using one of the world's most powerful laser facilities, a team led by University of Chicago scientists experimentally confirmed one of the most popular theories for cosmic magnetic field generation: the turbulent dynamo. By creating a hot turbulent plasma the size of a penny, that lasts a few billionths of a second, the researchers recorded how the turbulent motions can amplify a weak magnetic field to the strengths of those observed in our sun, distant stars, and galaxies.
Confirming decades of numerical simulations, the experiment revealed that turbulent plasma could dramatically boost a weak magnetic field up to the magnitude observed by astronomers in stars and galaxies.
Our Magnetic Universe | Daily Galaxy
When one or more of the outer (valence) electrons are stripped away from an atom we say the atom has become 'ionized'. It then exhibits a net positive electrical charge, and is called a 'positive ion'. On the other hand, if an extra electron is added onto a neutral atom, the combination then carries a net negative charge and is referred to as a 'negative ion'. The electrical forces between dissimilar ions are orders of magnitude stronger than any mechanical force such as that produced by gravity.
An electrical plasma is a cloud of ions and electrons that, under the excitation of applied electrical and magnetic fields, can sometimes light up and behave in some unusual ways. The most familiar examples of electrical plasmas are the neon sign, lightning, and the electric arc welding machine. The ionosphere of Earth is an example of a plasma that does not emit visible light. Plasma permeates the space that contains our solar system. The cloud of particles that constitutes the solar 'wind' is a plasma. Our entire Milky Way galaxy consists mainly of plasma. In fact 99% of the entire universe is plasma!
Plasma - The Fundamental State of Matter | electric cosmos
A turbulent dynamo of astrophysicists settled science debate on cosmic magnetism
3-D radiation magneto-hydrodynamic FLASH simulation of the experiment, performed on the Mira supercomputer at Argonne National Laboratory. The values demonstrate strong amplification of the seed magnetic fields by turbulent dynamo.
Measuring the magnetized universe | MIT
Magnetic fields are ubiquitous in the Universe. The energy density of these fields is typically comparable to the energy density of the fluid motions of the plasma in which they are embedded, making magnetic fields essential players in the dynamics of the luminous matter. The standard theoretical model for the origin of these strong magnetic fields is through the amplification of tiny seed fields via turbulent dynamo to the level consistent with current observations.
However, experimental demonstration of the turbulent dynamo mechanism has remained elusive, since it requires plasma conditions that are extremely hard to re-create in terrestrial laboratories. Here we demonstrate, using laser-produced colliding plasma flows, that turbulence is indeed capable of rapidly amplifying seed fields to near equipartition with the turbulent fluid motions. These results support the notion that turbulent dynamo is a viable mechanism responsible for the observed present-day magnetization.
Laboratory evidence of dynamo amplification of magnetic fields in a turbulent plasma