From: LARRY KLAES (ljk4@msn.com)
Date: Sun Apr 21 2002 - 06:28:12 PDT
----- Original Message -----
From: Space Environment Center
Sent: Sunday, April 21, 2002 2:45 AM
To: advisory-list-send@dawn.sec.noaa.gov
Subject: Space-Weather-Bulletin
ZCZC SWXADVBUL
TTAA00 KWNP 210550
Official Space Weather Advisory issued by NOAA Space Environment Center
Boulder, Colorado, USA
SPACE WEATHER ADVISORY BULLETIN #02- 1
2002 April 20 at 11:44 p.m. MDT (2002 April 21 0544 UTC)
**** MAJOR SOLAR FLARE AND SOLAR RADIATION STORM ****
SPACE WEATHER BULLETIN #02 - 1
2002 April 20 at 11:19 p.m. MDT (2002 April 21 0519 UTC)
**** MAJOR SOLAR FLARE AND SOLAR RADIATION STORM ****
A major solar flare occurred at 7:21 pm MDT (21/0151 UTC) on 20 April.
The resulting radio blackout reached the R3 level on the NOAA scale.
The flare was shortly followed by a strong solar radiation storm which
has reached the S3 level on the NOAA scale and is continuing in
progress at this time.
R3 radio blackouts result in widespread HF radio communication outages
on the dayside of the Earth and can also degrade low frequency
navigation signals.
S3 solar radiation storms can lead to single-event upsets in spacecraft
electronics, noise in spacecraft imaging systems, and reduction in the
efficiency of solar panels. Radiation storms also cause degraded HF
radio propagation in the polar regions and may be of some concern to
aircraft on polar routes.
Data used to provide space weather services are contributed by NOAA,
USAF, NASA, NSF, USGS, the International Space Environment Services
and other observatories, universities, and institutions. More
information is available at SEC's Web site http://sec.noaa.gov or
(303) 497-5127. The NOAA Public Affairs contact is Barbara McGehan
at bmcgehan@boulder.noaa.gov or (303) 497-6288.
This archive was generated by hypermail 2.1.2 : Sun Apr 21 2002 - 06:36:06 PDT