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| A past solar flare seen erupting from the sun on June 20, 2013. (Image credit: NASA Goddard) |
A surprise solar flare has burst from an area of dense magnetism on the
sun’s surface, causing a temporary radio blackout in parts of Australia and
all of New Zealand.
The M5-class, medium-strength solar flare was
recorded by NASA's Solar Dynamics Observatory
as it erupted from the sunspot AR3141 at 7:11 p.m. ET on Sunday (Nov. 6).
The flare created a rush of radiation that ionized Earth’s atmosphere,
according to spaceweather.com.
Sunspots are dark regions on the sun's surface where powerful magnetic
fields, created by the flow of electrical charges, knot into kinks before
suddenly snapping. The resulting release of energy launches bursts of
radiation called solar flares and explosive jets of solar material called
coronal mass ejections (CMEs). A CME did accompany this flare, but it was
not aimed at Earth.
The solar flare erupted unexpectedly and took scientists by surprise.
"Our apologies there was no alert for this event. The flare was impulsive,”
the solar activity tracking website SpaceWeatherLive
wrote on Twitter.
The
National Oceanic and Atmospheric Administration
(NOAA) classifies solar flares in five categories — A, B, C M and X — based
on the intensity of the X-rays they release, with each level having 10 times
the intensity of the last. TK
Once they reach Earth, X-rays and ultraviolet radiation produced by solar
flares ionize atoms in our upper atmosphere, making it impossible to bounce
high-frequency radio waves from them and creating a radio blackout. Radio
blackouts occur over the areas lit by the sun during the time of the flare,
and they are classified from R1 to R5, according to severity. This most
recent flare caused a moderate R2 blackout.
Solar activity, which astronomers have tracked since 1775, rises and falls
according to a roughly 11-year cycle. Solar activity has been especially
high recently, with sunspot numbers nearly twice those of
NOAA predictions.
The increased activity has sent waves of high-energy plasma and X-ray bursts
slamming into Earth's magnetic fields, downing Starlink satellites,
triggering radio blackouts and causing auroras as far south as Pennsylvania,
Iowa and Oregon.
And many more flares will likely lash Earth in the coming years. The sun's
activity is projected to steadily climb, reaching an overall maximum in
2025, before decreasing again.
This ramp-up in activity means that, on the night of a solar storm, the
northern lights will be visible much farther south than usual. This is
because Earth's magnetic field gets compressed slightly by the waves of
highly energetic particles, which ripple down magnetic field lines and
agitate molecules in the atmosphere. This then releases energy in the form
of light to create colorful shifting curtains in the night sky.
Source: Link
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Space & Astrophysics