De Volkskant, Saturday 2 May, 1998

Tornado's on the Sun, Solar wind on Earth

Tornado's with gusts up to hundred fifty kilometers a second rage around in the polar areas of the sun British astronomers made this conclusion from measurements taken with the European-American SOHO satellite. The Sun tornado's might form the base of the so called fast solar wind: ionized particles which are with high velocity blown away by the sun.

SOHO (Solar and Heliospheric Observatory) was launched in December 1995 and continually observes the sun for already two years with a large battery of instruments. With one of these instruments accurate measurements have been taken of the hot oxygen atoms in the atmosphere of the sun.

Astronomers of the Rutherford Appleton Laboratory and the University of Cambridge announce that they observed the gas atoms with in creasing velocity spiraled away from the Sun.

Despite the high velocity, the sun tornado's are less destructive then their earthly family members. The density of the atmosphere is very low. The discovery is especially important for a better understanding of the solar wind. This influences the magnetic field of the earth and causes disturbing of radio communication.

The American space organization NASA and her European counterpart ESA decided this month to extend the SOHO-project with three years, until 2003. This will give solar astronomers the opportunity to also study the sun during a period of high activity.

---