The Sun, our nearest star, provides us with warmth and light. Though it was long thought to be eternally changeless, at its syrface, immense storms of matter and energy bigger than the Earth, toss and turn the surface in cyclonic fury. Sunspots are the most well known hints that the Sun's surface is constantly changing. Larger than the Earth and with magnetic fields 10,000 times stronger than the Earth's, sunspots are places where the Sun's own magnetic field is especially concentrated. The number of spots on the surface comes in cycles lasting from 6 to 11 years between times of "sunspot maximum". For reasons that are not fully understood by scientists, solar flares can erupt near sunspots. In a matter of minutes, these storms release more energy than a dozen hydrogen bombs. Some of the gas heated by the flares remain trapped near the surface by concentrated magnetic fields that act like bottles. But in other storm events, perhaps also related to solar flares, matter can be hurled out into space at millions of kilometers per hour in what scientists call Coronal Mass Ejections or CME's. Both solar flares and CME's can be very disruptive to human activity on Earth and in space. Traveling at the speed of light , intense blasts of X-rays from solar flares reach the Earth in only eight minutes and can cause both the familiar "northern lights" auroral displays and disrupt radio communications. About 3 or 4 days later, the matter from the CME's may arrive near the Earth. This plasma of charged particles can buffet and change the shape of the Earth's magnetic field in space and also produce adverse affects such as electrical power outages and satellite outages.
This site was hosted by the NASA Ames Research Center from 1994-2018 and is now hosted by:
Curator: Al Globus
If you find any errors on this page contact Al Globus.
