Winds 'whip across Sun's surface'
news.com.au
16may02
GASEOUS winds charged with electricity speed across the surface of the Sun at more 300,000
kilometres an hour, NASA has announced.
"This discovery completely changes our understanding of coronal loops, immense,
arch-shaped structures of electrified gas that comprise the Sun's outer atmosphere
(corona)," said researcher Amy Winebarger.
The powerful winds were observed by the American probe TRACE (Transition Region and
Coronal Explorer) and the Euro-American probe SOHO (Solar and Heliospheric Observator).
Astronomers who conducted research at the Harvard-Smithsonian Centre for Astrophysics, in
Cambridge, Massachusetts, said the winds were more significant than gravity in determining
the density of the atmosphere.
The latest findings increase "our understanding of the corona, which is the location
of explosive solar activity that occasionally disrupts high-technology systems at
Earth," said Winebarger, referring to effects on the Earth's magnetic field.
The Sun's gravity at its visible surface is about 28 times stronger than that at the
Earth's surface. A 68 kg person would face an epic struggle to support 1,900 kg if he or
she could somehow stand on the solar surface.
For the Earth's atmosphere to behave similarly, winds over 4,800 kph would be required on
the surface. END OF REPORT
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