STD-AstroAlert: Intense Solar Flare Prompts Warnings

[PeterKuklok]

A s t r o A l e r t

07 September 2005

Solar Terrestrial Dispatch
www.spacew.com


INTENSE SOLAR FLARE PROMPTS WARNINGS

A very strong class X17.1 solar flare exploded on the Sun at 17:40 UTC
(1:40 pm EDT). This is a significant event. Very few solar flares ever reach
the X-class rating, and far fewer ever exceed an X10 level. Only a few solar
flares each solar cycle (a 10-year period) exceed an X10 rating. An X17 solar
flare is 17 times more intense in x-rays than a class X1.0 (which is, by
itself, a very energetic event). This particular event was strong enough to
saturate one of the x-ray sensors on the GOES spacecraft and very nearly
saturated both sensors. This intense solar flare was visible in white-light
by observers at Holloman solar observatory in New Mexico.

This event was associated with intense radio emissions and a strong
high-velocity coronal mass ejection that was ejected well to the southeast of
the Earth. Despite the poor location of this event, there is a chance the
extreme western flanking edge of the associated shock wave may reach the
Earth sometime on 9 September. Prior to that time, energetic protons from the
solar flare may begin reaching the Earth and result in an increase in the
radiation environment in the near-Earth space environment. Although no
significant geomagnetic or auroral storming is expected this time, additional
possible major solar flares from this region during the next two weeks could
easily provide the impetus for very strong space weather storms.

The sunspot complex responsible for this event is an old "friend," by
the name of Region 10798, which was responsible for producing periods of
severe geomagnetic storming last month. It's longevity is impressive, as most
sunspot groups do not survive this long. As it came into view, NOAA assigned
a new number to this region. It will hereafter be known as Region 10808 (nick
named Region 808).

The fact that this region has produced such a powerful flare suggests
that it contains a complex magnetic topology. It is just now coming into view
around the eastern limb of the Sun and is still too close to the limb to
discern any significant detail. We expect additional major flares and
possibly additional significant major flares of X10 or greater intensities,
during the next week.

Region 808 will gradually rotate across the solar disk during the next
two weeks. During that time, if it retains its volatility, it may produce
some serious effects at the Earth. The health of spacecraft may be
compromised if additional extreme events are observed. Power grids may suffer
from induced currents caused by intense geomagnetic storms. Radio
communications may suffer from strong scintillation and absorption. And large
regions of the Earth may be able to spot periods of auroral activity
("northern lights"). Region 808 will be best positioned to inflict strong
impacts on the Earth in approximately another 4 to 5 days, with maximal
effects possible from roughly 11 September through 18 September. Spacecraft
will remain vulnerable to potential strong space radiation storms through to
about 23 September.

It is perhaps produnt to note that these strong solar flares pose no
known significant health threat to humans on the Earth. There is a greater
threat to human health for astronauts on the International Space Station, but
even they are relatively well protected in the heavily shielded regions of
the space station. The combined effects of the Earth's magnetic field and the
ionosphere protect human activities on Earth. However, some sensitive
industries on the ground can be adversely effected, including electrical
power generation facilities, ionospheric radio communications, satellite
communications, cellular phone networks, sensitive fabrication industries,
and others. During the next two weeks, these industries may see an increase
in anomalous incidents that may be attributed to space weather effects.


** End of AstroAlert **

[PeterKuklok]

MAJOR SOLAR FLARE ALERT

Issued: 23:30 UTC, 07 September 2005
Solar Terrestrial Dispatch
www.spacew.com

Synopsis:

A significant major class X17.1/3B (optical is an estimate due to limb
proximity) solar flare erupted from the Sun at 17:40 UTC on 7 September. A high velocity coronal mass ejection was also associated with this event. The
trajectory is dominantly well to the southeast of the Earth. At the most,
we may see a minor grazing impact from the extreme western edge of the shock
sometime on 9 September (perhaps mid-day-ish, although the uncertainty is
large). This event was associated with a confirmed white-light component, as
reported by Holloman solar observatory. The white-light flare was visible
directly on the east limb (at E89). In addition, intense radio emissions
were observed with this event, including a 27,000 sfu tenflare and a 37,000
sfu burst at 15.4 GHz. An intense Type II radio burst was observed at 17:42
UTC and had an associated estimated shock velocity of 1860 km/sec. A moderate
Type IV burst was also observed at 17:50 UTC.

Region 10808 is responsible for this event and is synonymous with old
Region 10798. Region 808 is expected to continue to produce occassional major
flare activity during the next two weeks (possibly X10 or greater). It has
been a fairly prolific producer of energetic events, as has been evidenced by
back-sided coronal mass ejection activity during the last two weeks. Until it becomes more clearly visible during the next several days, this assumption will
hold. It is presently too close to the limb to discern any detail.


** End of Alert **

[Dennis A.]

und was heist das jetzt auf deutsch?

[Sinclair]

kurze Zusammenfassung, dieser X17,1 war mit einer der größen Events die je registriert worden und es ist wahrscheinlich das in den nächsten 2 Wochen weitere Major Flares folgen werden mit möglichen Auswirkungen auf alles was im Orbit rumfliegt und hier auf der Erde Störungen bzw Ausfälle bei Stromwerken und Telekommunikation, desweiteren besteht dann die Möglichkeit auf Polarlichtern vielleicht auch in unseren Regionen. Auf Menschen der Erde selbst hat dieser Ausbruch keine negativen gesundheitlichen Effekte, jedenfalls solange nicht wie unser Erdmagnetfeld noch so einigermaßen fit ist, anders sieht es bei Astronauten aus die zZ im Weltraum sind die sollten sich ein geschütztes Plätzchen suchen ansonsten leuten sie im Dunkeln selbst