NASA Spacecraft Capture an Earth
Directed Coronal Mass Ejection
The SOHO LASCO C2 instrument captured this
image of the Earth-directed CME. SOHO's coronographs are able to take images of
the solar corona by blocking the light coming directly from the Sun with an
occulter disk. The location of the actual sun is shown with an image taken by
SDO.Image Credit: ESA & NASA/SOHO, SDO
On August 20, 2013 at 4:24 am EDT, the sun erupted with an Earth-directed
coronal mass ejection or CME, a solar phenomenon which can send billions of
tons of particles into space that can reach Earth one to three days later.
These particles cannot travel through the atmosphere to harm humans on Earth,
but they can affect electronic systems in satellites and on the ground.
Experimental
NASA research models, based on observations from NASA’s Solar Terrestrial
Relations Observatory show that the CME left the sun at speeds of around 570
miles per second, which is a fairly typical speed for CMEs.
Earth-directed
CMEs can cause a space weather phenomenon called a geomagnetic storm, which
occurs when they funnel energy into Earth's magnetic envelope, the
magnetosphere, for an extended period of time. The CME’s magnetic fields peel
back the outermost layers of Earth's fields changing their very shape. In the
past, geomagnetic storms caused by CMEs of this strength have usually been
mild.
Magnetic
storms can degrade communication signals and cause unexpected electrical surges
in power grids. They also can cause aurora.
NOAA's
Space Weather Prediction Center (http://swpc.noaa.gov) is the U.S. government's
official source for space weather forecasts, alerts, watches and warnings.
Updates
will be provided if needed. Aug. 20, 2013 NASA
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