1 SOLAR Storms The Sun is the star at the center of our solar system The Sun’s powerful energy warms Earth and gives us light
IN OCTOBER 2003 A HUGE SOLAR FLARE EXPLODED FROM THE SUN ITS TONGUES OF BURNING GAS LEAPED THOUSANDS OF MILES INTO SPACE THE FLARE’S EXPLOSION PRODUCED MORE POWER THAN TEN MILLION HYDROGEN BOMBS IT WAS THE SUN’S MOST POWERFUL EXPLOSION IN THIRTY YEARS When the flare exploded it sent an enormous cloud blasting out into space The cloud contained billions of electrically charged particles It also contained powerful waves of radiation a kind of energy In less than a day the cloud slammed into Earth’s magnetic field The field is a set of invisible lines around Earth where magnetism can be felt Magnetism is a force that pulls objects together or pushes them away from one another This computer-generated image shows a solar flare left exploding out toward Earth right Earth’s magnetic field is shown in blue Energy from a solar flare can disturb Earth’s magnetic field disrupting electrical and communication systems on Earth 7
The collision set off a big magnetic storm a disturbance of the magnetic field This kind of storm can hurt electrical power systems For instance in 1989 a magnetic storm damaged power lines in Quebec Canada People in some parts of Quebec had no electricity for nine hours Magnetic storms can cause other problems too They can damage or disrupt radio communications Global Positioning Systems GPS and cell phone service BRACING FOR TROUBLE Astronomers watched closely as the huge solar flare exploded in October 2003 They tracked the flare so they could warn people about it For instance they told workers at power companies to prepare their equipment for a magnetic storm With advance warning power companies could take action to keep the electricity from going out Seven Wonders of the Sun and Other Stars Luckily the magnetic storm was not as bad as astronomers had feared The charged particles that caused the storm did not hit Earth’s magnetic field directly They hit at an angle causing less damage The storm weakened quickly Its blast of energy soon died away It caused only minor damage to communications systems But the magnetic storm also had a positive effect It created spectacular auroras Auroras are 8 AWESOME Auroras Auroras are swirling curtains of colorful lights in the night sky They are usually green but can also be red purple blue or white Auroras occur when the solar wind carries electrically charged particles from the Sun to Earth’s magnetic field When the particles enter this field they move toward the north and south poles As they move the particles rub against gases in Earth’s atmosphere The electrical charges in the particles cause the atmosphere to glow Some auroras cover thousands of miles Normally auroras appear only near the north and south poles That’s why auroras are also called northern lights and southern lights When a solar flare causes a big magnetic storm many more particles than normal enter Earth’s magnetic field Then people in many other places can see these beautiful colored lights
An aurora makes a spectacular display in the sky over Portage Lake in the Chugach Mountains of Alaska Auroras are common near the north and south poles at the top and bottom of Earth’s magnetic field An aurora happens when particles from the Sun hit the magnetic field and cause the atmosphere to glow bands of glowing colored lights in the sky People in many parts of the world saw swirling curtains of light when the magnetic storm hit The beauty of the shimmering dancing lights was awe inspiring When I was eight years old I watched auroras swirling in the winter skies of Minnesota They looked like glowing curtains of colored light I was lucky to see them so far from the North Pole Later on I learned that the auroras I saw were caused by a big solar flare exploding from the Sun Lee Hansen science writer 2008 Solar Storms 9