China's FAST telescope detects coherent interstellar magnetic field
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Aerial photo taken on December 19, 2021 shows a panoramic view of China's Five-hundred-meter Aperture Spherical Radio Telescope under maintenance in southwest China's Guizhou Province.
Using the Five-hundred-meter Aperture Spherical Radio Telescope (FAST), also dubbed as the "China Sky Eye," scientists have obtained accurate magnetic field strength in molecular cloud, a region of the interstellar medium that seems ready to form stars.
Employing the technique of HI Narrow Self Absorption (HINSA), they achieved a clear detection of the Zeeman effect – the splitting of a spectral line into several components of frequency in the presence of a magnetic field. It is the only direct probe of interstellar magnetic field strength.
The result suggested that such clouds achieve supercritical state, a critical point when they collapse into stars, happened earlier than previously thought based on the standard model.
The study was published in Nature on Thursday.
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Aerial photo taken on December 19, 2021 shows China's Five-hundred-meter Aperture Spherical Radio Telescope under maintenance in southwest China's Guizhou Province.
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Photo taken on December 19, 2021 shows China's Five-hundred-meter Aperture Spherical Radio Telescope under maintenance in southwest China's Guizhou Province.
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