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  • Musical Tone Music Narrator: Solar flares may seem like far-away events, but they can

  • damage satellites and even ground-based technologies and power grids. Every 11 years, as the sun

  • reaches it's maximum activity they become bigger and more common, and that increases

  • the chances that one will significantly affect Earth. So what are these solar eruptions?

  • A solar flare is basically an explosion on the surface of the sun ranging from minutes

  • to hours in length. Large flares can release enough energy to power the entire United States

  • for a million years. Flares happen when the powerful magnetic fields in and around the

  • sun reconnect. They're usually associated with active regions, often seen as sun spots,

  • where the magnetic fields are strongest. Flares are classified according to their strength.

  • The smallest ones are B-class, followed by C, M and X, the largest. Similar to the Richter

  • scale for earthquakes, each letter represents a ten-fold increase in energy output. So an

  • X is 10 times an M and 100 times a C. Within each letter class, there is a finer scale

  • from 1 to 9. C-class flares are too weak to noticeably affect Earth. M-class flares can

  • cause brief radio blackouts at the poles and minor radiation storms that might endanger

  • astronauts. It's the X-class flares that are the real juggernauts. Although X is the last

  • letter, there are flares more than 10 times the power of an X1, so X-class flares can

  • go higher than 9. The most powerful flare on record was in 2003, during the last solar

  • maximum. It was so powerful that it overloaded the sensors measuring it. They cut-out at

  • X17, and the flare was later estimated to be about X45. A powerful X-class flare like

  • that can create long lasting radiation storms, which can harm satellites, and even give airline

  • passengers flying near the poles small radiation doses. X flares also have the potential to

  • create global transmission problems and world-wide blackouts. The seriousness of an X-class flare

  • pointed at Earth is why NASA and NOAA constantly monitor the sun. NASA's Heliophysics fleet

  • of spacecraft can now see the sun from every side and in many different wavelengths. This

  • unprecedented coverage is enabling scientists to predict and detect space weather events

  • like flares and CMEs with ever greater accuracy. With advance warning, governments and companies

  • can take steps to protect their technological infrastructure, so that the worst scenarios

  • will never happen. Beeping Beeping

Musical Tone Music Narrator: Solar flares may seem like far-away events, but they can

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