Nov10
The Sun is not a perfect sphere
SYDNEY: Scientists using a space observatory orbiting the Sun, have calculated the star’s roundness with unprecedented precision, and found that it is not a perfect sphere. The research could lead to techniques for measuring the Sun’s elusive internal core.
Though the Sun is more perfectly round than any of the planets, their new study – reported today in the U.S. journal Science – shows that in years of high solar activity it develops a thin “cantaloupe skin” that significantly changes how wide it is around the equator.
Strong gravity
“The Sun is the biggest and smoothest natural object in the solar system, perfect at the 0.001 per cent level because of its extremely strong gravity,” said study lead author Hugh Hudson of the University of California, Berkeley, in the USA. “Measuring its exact shape is no easy task.”
The team achieved the calculation by analysing data from NASA’s Reuven Ramaty High-Energy Solar Spectroscopic Imager (RHESSI), an X-ray/gamma-ray space telescope…
Source : Cosmos
