What Are Coronal Mass Ejections, or CMEs?
Learn more about these huge solar explosions.
Encyclopædia Britannica, Inc.
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NASA/GSFC/SDO/AIAAn erupting solar prominence observed by the Solar Dynamics Observatory satellite on March 30, 2010.
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University College Cork, Ireland (A Britannica Publishing Partner)An overview of solar flares.
Transcript
The Sun’s magnetic fields are in constant flux––flowing in complicated ropes that can break through the Sun’s surface before dipping back down.
Sometimes those arcs of magnetic field can rapidly realign, creating enormous blasts of energy that move away from the Sun.
This can result in the Sun emitting sudden flashes of light, called solar flares.
Another such blast drives off solar material called plasma.
These events are known as coronal mass ejections, or CMEs.
Forming massive expanding bubbles of hot gas that escape the gravitational pull of the Sun, CMEs can travel over a million miles per hour.
Although this is slower than the speed of the light and materials emitted by solar flares, coronal mass ejections can have much more dramatic effects on Earth.
They have the potential to overload power grids, disrupt communication channels, and interact with Earth’s own magnetosphere…
… so astronomers pay close attention to the rare CME pointed toward Earth.
Not all effects are unwelcome, however.
When a balloon-shaped CME reaches Earth, our planet is enveloped in supercharged particles that interact with our own magnetic field.
Certain magnetic patterns can force these particles down toward Earth’s poles.
The captivating light of the auroras is the result, sending colorful trails across the skies of the North and South Poles.
One of the strongest recorded CMEs, in 1859, caused auroral lights that were seen all the way to the tropics!
Sometimes those arcs of magnetic field can rapidly realign, creating enormous blasts of energy that move away from the Sun.
This can result in the Sun emitting sudden flashes of light, called solar flares.
Another such blast drives off solar material called plasma.
These events are known as coronal mass ejections, or CMEs.
Forming massive expanding bubbles of hot gas that escape the gravitational pull of the Sun, CMEs can travel over a million miles per hour.
Although this is slower than the speed of the light and materials emitted by solar flares, coronal mass ejections can have much more dramatic effects on Earth.
They have the potential to overload power grids, disrupt communication channels, and interact with Earth’s own magnetosphere…
… so astronomers pay close attention to the rare CME pointed toward Earth.
Not all effects are unwelcome, however.
When a balloon-shaped CME reaches Earth, our planet is enveloped in supercharged particles that interact with our own magnetic field.
Certain magnetic patterns can force these particles down toward Earth’s poles.
The captivating light of the auroras is the result, sending colorful trails across the skies of the North and South Poles.
One of the strongest recorded CMEs, in 1859, caused auroral lights that were seen all the way to the tropics!
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