- i will be at Tuckahoe tonight - see the alert below - hope to see you there
- bundle up!
A s t r o A l e r t
Solar Terrestrial Dispatch
05 November 2001
Details, images, and movies:
A significant and powerful solar flare (X-class event, the most
class of x-ray flares rated) exploded from active sunspot complex number
at 16:19 UTC (11:19 pm EST) on 04 November. Less than 20 minutes later, a
barrage of highly energetic particles (protons with energies greater than
million electron volts) travelling at near the speed of light began
the near-Earth space environment. At the same time, a large coronal mass
ejection (CME) was observed by the Solar and Heliospheric Observatory
spacecraft's Large Angle and Spectrometric Coronagraph Experiment (LASCO)
cameras. The trajectory of the ejected mass was quickly determined to be
Earth-directed based on the halo of light that was observed propagating
outward from the Sun with each of the LASCO images that were received.
The velocity of the coronal mass ejection was estimated to be
high (at least 1,000 km/sec). The ejected mass formed a shock wave in the
inner-corona of the Sun. The shock wave excited electrons as it propagated
outward, resulting in a loud radio emission known as a Type II sweep
frequency event. As the shock wave propagated outward to regions of lower
electron density, the observed radio emissions also decreased in frequency.
Through the use of models that describe how electron densities decrease
altitude through the solar corona, it is possible to estimate the velocity
with which the responsible shock wave propagated outward through the
The results thus far suggest the shock wave may have been travelling at a
velocity in excess of 1,300 kilometers per second (4.68 million kilometers
per hour or almost 3 million miles per hour). A spacecraft moving that fast
(still a dream by todays standards) would be able to traverse the distance
from the Earth to the Moon in less than 5 minutes!
The CME is predicted to impact the Earth near 06:00 UTC on 06 November
(11 pm EST on **05** November for North American observers), +/- up to 8
hours. The arrival of this disturbance is expected to produce a potentially
strong auroral storm. Observers interested in watching for the "Northern
Lights" are therefore encouraged to watch the skies of 05 and 06 November
activity. A fairly strong light show is possible on those dates.
Additional information, including images and movies of the solar
are available at: http://www.spacew.com/astroalert.html
Additional major solar flares are possible over the next 3 to 5 days.
A middle latitude auroral activity warning has been issued and is
MIDDLE LATITUDE AURORAL ACTIVITY WARNING
ISSUED: 06:20 UTC, 05 NOVEMBER 2001
*** POTENTIAL FOR HIGH ACTIVITY EXISTS ***
VALID BEGINNING AT: 00:00 UTC ON 06 NOVEMBER (7 pm EST on 05 November)
VALID UNTIL: 19:00 UTC ON 07 NOVEMBER
HIGH RISK PERIOD: 06 NOVEMBER (UTC DAYS)
MODERATE RISK PERIOD: 05 - 07 NOVEMBER
PREDICTED ACTIVITY INDICES: 12, 50, 20, 12 (05 - 08 NOVEMBER)
POTENTIAL MAGNITUDE OF MIDDLE LATITUDE AURORAL ACTIVITY: MODERATE - HIGH
POTENTIAL DURATION OF THIS ACTIVITY: MAIN BELT = 12 TO 18 HOURS
MINOR BELT = 18 TO 24 HOURS
ESTIMATED OPTIMUM OBSERVING CONDITIONS: NEAR LOCAL MIDNIGHT
EXPECTED LUNAR INTERFERENCE: MODERATE
OVERALL OPPORTUNITY FOR OBSERVATIONS FROM MIDDLE LATITUDES: FAIR TO GOOD
AURORAL ACTIVITY *MAY* BE OBSERVED APPROXIMATELY NORTH OF A LINE FROM...
SOUTHERN OREGON TO NORTHERN UTAH TO NORTHERN COLORADO TO NORTHERN KANSAS
TO MISSOURI TO KENTUCKY TO VIRGINIA.
ACTIVITY *MAY* ALSO BE OBSERVED APPROXIMATELY NORTH OF A LINE FROM...
SOUTHERN FRANCE TO NORTHERN ITALY TO SLOVENIA TO HUNGARY TO NORTHERN
ROMANIA TO NORTHERN MOLDOVA TO UKRAINE TO CENTRAL RUSSIA. MOST OF NEW
ZEALAND AND EXTREME SOUTHERN REGIONS OF AUSTRALIA MAY ALSO SPOT PERIODS
OF ACTIVITY. THERE IS ALSO A *SLIGHT* CHANCE EXTREME SOUTHERN REGIONS OF
CHILE AND ARGENTINA MAY SPOT BRIEF PERIODS OF ACTIVITY.
Auroral activity is expected to intensify to storm levels following
anticipated arrival of a potentially strong coronal mass ejection early in
the UTC day of 06 November (evening hours of 05 November over North
The disturbance is expected to last approximately 18 to 24 hours. The moon
roughly 70% illuminated during this period of time and will therefore prove
to be somewhat of a hinderance to observing activity once it rises higher
the sky. Nevertheless, activity could become intense enough at times to
override the influence of the moon.
This warning will remain in effect until 19:00 UTC on 07 November. It
will then be updated or allowed to expire.
PLEASE REPORT OBSERVATIONS OF AURORAL ACTIVITY TO:
o Monitor real-time conditions and report sightings using software at:
o On-line global discussion forum:
o Chat in real-time with others using IRC at:
and join the #aurora channel (type /join #aurora in the IRC software).
o Real-time notification of events via Digital SMS:
** End of AstroAlert **
I'll try to be out there tonight. Wouldn'tcha know it, moonrise
is in the middle of the evening, which could wipe out all but the
- please check out the 2 websites below - it appears we have an excellent
chance for auroras tonight. i plan to be at tuckahoe to witness the
hope to see you there.