First Image Of Turbulent Gas In Milky Way Resembles Pit Of Writhing Snakes

In a groundbreaking image captured in eastern Australia, the violent swirling of the gas between the stars in our Milky Way has been shown to resemble a pit of writhing snakes.

AsianScientist (Oct. 12, 2011) – The violent swirling of the gas between the stars has been captured for the first time by Professor Bryan Gaensler of the University of Sydney, Australia, and his team, using a CSIRO radio telescope in eastern Australia.

The groundbreaking image, published in the journal Nature, shows that the turbulent gas in our Milky Way looks like a pit of writhing snakes.

“This is the first time anyone has been able to make a picture of this interstellar turbulence,” said Prof. Gaensler.

Turbulence makes the Universe magnetic, helps stars form, and spreads the heat from supernova explosions through the Galaxy, he explains.

“We now plan to study turbulence throughout the Milky Way. Ultimately this will help us understand why some parts of the Galaxy are hotter than others, and why stars form at particular times in particular places,” he added.

Gaensler and his team used CSIRO’s Australia Telescope Compact Array to study a region of our Galaxy about 10,000 light-years away in the constellation Norma.

The radio telescope was tuned to receive radio waves that come from the Milky Way. As these waves travel through the swirling interstellar gas, the researchers measured the polarization changes over an area of sky and used them to make a spectacular image of overlapping entangled tendrils, resembling writhing snakes.

In the photo, the ‘snakes’ are regions of gas where the density and magnetic field are changing rapidly as a result of turbulence. They also show how fast the gas is churning – an important number for describing the turbulence.

Team member Blakesley Burkhart, a graduate student from the University of Wisconsin, made several computer simulations of turbulent gas moving at different speeds. These simulations resembled the ‘snakes’ picture, with some matching the real picture better than others.

By picking the best match, the team concluded that the speed of the swirling in the turbulent interstellar gas is around 70,000 kph – relatively slow by cosmic standards.

The article can be found at: Gaensler BM et al. (2011) Low-Mach-number turbulence in interstellar gas revealed by radio polarization gradients.

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Source: CSIRO.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.

Anusuya Das received a Ph.D. in Biological Engineering from Massachusetts Institute of Technology (MIT), USA, and a B.A. in Bioelectrical/Cellular-Molecular Engineering from Arizona State University, USA. Anusuya is currently a post-doctoral researcher at the University of Virginia, USA.

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