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Fw: NASA: SUN UNLEASHES RECORD SUPERFLARE (fwd)



Hi All,

    To compliment Peter's recent post on the solar flare, see message below.

73,
Brian, N5ZGT
Albuquerque, NM

>
> THE FOLLOWING RELEASE WAS RECEIVED FROM NASA HEADQUARTERS, WASHINGTON,
> DC, AND IS FORWARDED FOR YOUR INFORMATION.  (FORWARDING DOES NOT IMPLY
> ENDORSEMENT BY THE AMERICAN ASTRONOMICAL SOCIETY.)
> Steve Maran,
> American Astronomical Society
>
> Dolores Beasley
> Headquarters, Washington, DC                 April 3, 2001
> (Phone: 202/358-1753)
>
> Bill Steigerwald
> Goddard Space Flight Center, Greenbelt, MD
> (Phone: 301/286-5017)
>
> RELEASE: 01-66
>
> SUN UNLEASHES RECORD SUPERFLARE,
> EARTH DODGES SOLAR BULLET
>
>      The Sun blasted one of its largest flares in 25 years
> from the same region harboring the largest sunspot of the
> current solar cycle Monday evening.
>
> The region, designated active region 9393, has continued to
> rotate with the Sun and is no longer in line with the Earth,
> so most of the flare's energy was directed away from our
> planet. However, radiation from the flare temporarily
> disrupted radio communications, and flare-related events
> generated a storm of high-velocity particles that, in greater
> numbers and energies, can affect sensitive electronic
> equipment in space.
>
> "This explosion was estimated as an X-20 flare, and was as
> strong as the record X-20 flare on August 16, 1989, " said Dr.
> Paal Brekke, the European Space Agency Deputy Project
> Scientist for the Solar and Heliospheric Observatory (SOHO),
> one of a fleet of spacecraft monitoring solar activity and its
> effects on the Earth. "It was more powerful that the famous
> March 6, 1989 flare which was related to the disruption of the
> power grids in Canada."
>
> Monday's flare and the August 1989 flare are the most powerful
> recorded since regular X-ray data became available in 1976.
>
> Solar flares, among the solar system's mightiest eruptions,
> are tremendous explosions in the atmosphere of the Sun capable
> of releasing as much energy as a billion megatons of TNT.
> Caused by the sudden release of magnetic energy, in just a few
> seconds flares can accelerate solar particles to very high
> velocities, almost to the speed of light, and heat solar
> material to tens of millions of degrees.
>
> The flare erupted at 4:51 p.m. EDT Monday, and produced an R4
> radio blackout on the sunlit side of the Earth. An R4
> blackout, rated by the NOAA SEC, is second to the most severe
> R5 classification. The classification measures the disruption
> in radio communications. X-ray and ultraviolet light from the
> flare changed the structure of the Earth's electrically
> charged upper atmosphere (ionosphere). This affected radio
> communication frequencies that either pass through the
> ionosphere to satellites or are reflected by it to traverse
> the globe.
>
> The explosion, near the Sun's northwest limb (the upper right
> in SOHO images), was associated with an eruption of a cloud of
> electrified gas, called a coronal mass ejection, or CME, into
> space, but apparently not directed towards Earth.
>
> "We are perhaps lucky that this event didn't occur over the
> weekend, when the resulting CME would almost certainly have
> been aimed towards Earth," said Brekke. "A smaller flare-
> related CME event in March 1989 caused major power failures in
> Canada, and subsequent smaller events have disrupted
> communication and navigation satellites."
>
> Solar ejections are often associated with flares and sometimes
> occur shortly after the flare explosion. CMEs are clouds of
> electrified, magnetic gas weighing billions of tons ejected
> from the Sun and hurled into space with speeds ranging from 12
> to 1,250 miles per second. Depending on the orientation of the
> magnetic fields carried by the ejection cloud, Earth-directed
> CMEs cause magnetic storms by interacting with the Earth's
> magnetic field, distorting its shape and accelerating
> electrically charged particles (electrons and atomic nuclei)
> trapped within.
>
> Severe solar weather is often heralded by dramatic auroral
> displays, northern and southern lights, and magnetic storms
> that occasionally affect satellites, radio communications and
> power systems. The flare and solar ejection has also generated
> a storm of high-velocity particles, and the number of
> particles with ten million electron-volts of energy in the
> space near Earth is now 10,000 times greater than normal. The
> increase of particles at this energy level still poses no
> appreciable hazard to air travelers, astronauts or satellites,
> and the NOAA SEC rates this radiation storm as a moderate S2
> to S3, on a scale that goes to S5.
>
> The SOHO project is an international cooperative program
> between NASA and the European Space Agency for the
> International Solar Terrestrial Science Program.
>
> For additional information and images regarding the flare,
> space weather and the giant sunspot, see:
>           http://sohowww.nascom.nasa.gov/hotshots/X17/
>                    http://www.spaceweather.com/
>          http://www.sel.noaa.gov/NOAAscales/index.html
>    http://www.noao.edu/outreach/press/pr01/img0101.html
>                         -end-
> ------------------------------------------------------------------
>
>
>

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