A research team led by the University of Iowa has confirmed “gusty winds” in space turbulence. Researchers contend that unexplained turbulence exists in space and for the first time ever, they have directly measured these “gusty winds” in a laboratory.
“Turbulence is not restricted to environments here on Earth, but also arises pervasively throughout the solar system and beyond, driving chaotic motions in the ionized gas, or plasma, that fills the universe,” says lead author Gregory Howes, assistant professor of physics and astronomy at the University of Iowa. “It is thought to play a key role in heating the atmosphere of the sun, the solar corona, to temperatures of a million degrees Celsius, nearly a thousand times hotter than the surface of the sun.”
Measuring the “gusty winds” in space turbulence will help astronomers better understand our solar system.
“Turbulence also regulates the formation of the stars throughout the galaxy, determines the radiation emitted from the super massive black hole at the center of our galaxy and mediates the effects that space weather has on the Earth,” Mr. Howes posits.
Researchers already know that violent emissions of charged particles from the sun, also known as coronal mass ejections, are the source of gusty space winds. According to NASA, coronal mass ejections are humongous bubbles of gas intertwined with magnetic field lines that are ejected from the sun over the course of several hours. The space agency points out that the existence of coronal mass ejections was not known until the space age. Evidence of these eruptions was gathered by a coronagraph on the 7th Orbiting Solar Observatory from 1971 to 1973.
These “gusty winds” have the power to impact satellite communications, air travel and the electric power grid on Earth. Solar storms, however, can also provide stunning auroras at the north and south poles on Earth.
NASA notes that the solar wind coming from the sun is approximately a million degrees Celsius and that it can travel as fast as 466 statute miles per second.
Mr. Howes adds that unlike wind gusts on the surface of the Earth, space turbulence is controlled by Alfven waves, which are moving disturbances of the plasma and magnetic field. Researchers contend that nonlinear interactions between Alfven waves moving up and down the magnetic field are an important building block of plasma turbulence, and modern theories of astrophysical turbulence are based on this fundamental idea.
“We have presented the first experimental measurement in a laboratory plasma of the nonlinear interaction between counter-propagating Alfven waves, the fundamental building block of astrophysical turbulence,” Mr. Howes notes.
The study’s findings were published today in the online edition of the journal Physical Review Letters.