Increased activity from CME shown here in form of increased X-Ray flux from the sun indicates we should be expecting a >6R event soon
Information
This data is measured by the
GOES-15 satellite which does monitor Solar X-Rays. This information is very
important in tracking solar flares. Large X-ray bursts cause short wave fades
for HF propagation paths through the sunlit hemisphere. Solar flares can also
trigger geomagnetic storms which produce aurora and nice openings on VHF.
What is a
Solar Flare?
A solar flare is a violent
explosion in the Sun's atmosphere with an energy equivalent to tens of millions
of hydrogen bombs. Solar flares take place in the solar corona and
chromosphere, heating plasma to tens of millions of kelvins and accelerating
the resulting electrons, protons and heavier ions to near the speed of light.
They produce electromagnetic radiation across the electromagnetic spectrum at
all wavelengths from long-wave radio to the shortest wavelength Gamma rays.
Most flares occur around sunspots, where intense magnetic fields emerge from
the Sun's surface into the corona. The energy efficiency associated with solar
flares may take several hours or even days to build up, but most flares take
only a matter of minutes to release their energy.
Solar Flare Classifications
Solar flares are classified as
A, B, C, M or X according to the peak flux (in watts per square meter, W/m2) of
100 to 800 picometer X-rays near Earth, as measured on the GOES spacecraft.
Each class has a peak flux ten times greater than the preceding one, with X
class flares having a peak flux of order 10-4 W/m2. Within a class there is a
linear scale from 1 to 9, so an X2 flare is twice as powerful as an X1 flare,
and is four times more powerful than an M5 flare. The more powerful M and X
class flares are often associated with a variety of effects on the near-Earth
space environment. Although the GOES classification is commonly used to
indicate the size of a flare, it is only one measure.
Coronal Mass
Ejection (CME) and earth effects.
A coronal mass ejection (CME)
is an ejection of material from the solar corona, observed with a white-light
coronagraph.
The material consists of
plasma consisting primarily of electrons and protons (in addition to small
quantities of heavier elements such as helium, oxygen, and iron), plus the
entrained coronal magnetic field. When the solar cloud reaches the Earth as an
ICME (Interplanetary CME), it may disrupt the Earth's magnetosphere,
compressing it on the dayside and extending the nightside tail. When the
magnetosphere reconnects on the nightside, it creates trillions of watts of
power which is directed back towards the Earth's upper atmosphere. This process
can cause particularly strong aurora also known as the Northern Lights (in the
Northern Hemisphere) and the Southern Lights(in the Southern Hemisphere). CME
events, along with solar flares, can disrupt radio transmissions, cause power
outages (blackouts), and cause damage to satellites and electrical transmission
lines.
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