[HCRA] Fw: [RACES] Solar Flare

[Daniel J. Sullivan]

----- Original Message ----- 
From: <NEDROG at aol.com>
To: <RACES at yahoogroups.com>
Sent: Wednesday, September 07, 2005 6:55 PM
Subject: [RACES] Solar Flare


>
>
> One of the largest solar flares on record occurred  earlier today
(Wednesday,
> September 7). Very active Region 808 produced a  powerful X17 flare (R4 on
> the R1 to R5 NOAA Scale) observed on the NOAA GOES  satellite at 1:40 pm
EDT.
> An R4 event typically occurs about 8 times per  11-year solar cycle.  This
> flare, the 4th largest in the last 15 years,  erupted just as the Region
808
> sunspot cluster was rotating onto the visible  disk of the sun.  Intense
radio
> emissions were also associated with this  flare.  A very bright and fast
coronal
> mass ejection was observed on  coronagraph imagery; however, the material
was
> not Earth directed.  An S1  to S2 (on a scale from S1 to S5) radiation
storm is
> expected following this  eruption, but is not expected to begin until late
on
> today (Wednesday September  7) or early Thursday (September 8).
>
> Impacts
>
> This event created a  complete blackout of high frequency (HF)
communications
> on the daylit side of  Earth.  Communications used by emergency services
> along the Gulf Coast may  have experienced problems due to this flare.
Low
> frequency navigation  systems may also have experienced a period of
significant
> degradation.
>
> Over the past two weeks, this active region produced a  series of
significant
> solar eruptions as it made its passage around the back  side of the Sun.
> Significant eruptions are expected in the coming days. Agencies  impacted
by space
> weather storms may experience disruptions over the next two  weeks. These
> include spacecraft operations, electric power systems, HF  communications,
and
> low-frequency navigation systems.
>
> NOAA National  Weather Service Operations
>
> The Space Weather Advisory Bulletins issued by  SEC are distributed to
> approximately 2,500 primary recipients around the  world.  These include
military
> and civilian space agencies, space agency  contractors, domestic and
> international airlines and power grid companies.   There is no requirement
for these
> recipients to notify SEC of any effects caused  by geomagnetic storms.
Impacts
> may not be learned for some time after an  event.
>
> As soon as the solar flare occurred, SEC began working on their  first
> alerts, by trying to determine: the magnitude of the flare; whether the
coronal
> mass ejections were heading toward the Earth; and if so, how strong they
would
> be when they did reach the Earth.  The alerts and forecasts are
continually
> updated as new information was received from satellites and other
sensors.
>
> Data used to provide space weather services are contributed by  NOAA, USAF
> (U.S. Air Force), NASA (National Aeronautics and Space  Administration),
NSF
> (National Science Foundation), USGS (U.S. Geological  Survey), the
International
> Space Environment Services (a consortium of 11 member  nations that
> facilitates near-real-time international monitoring and space  environment
prediction)
> and other observatories, universities, and institutions.  More information
is
> available on the SEC website at _http://sec.noaa.gov_
(http://sec.noaa.gov/)
>
>
>
>
>
>
> [Non-text portions of this message have been removed]
>
>
>
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