May 6 EVENT SUMMARY|
From Scott Paswaters (SOHO/LASCO)
1998/05/06 00:02 A bright partial halo CME appears in the C2 FOV.
Most of the material is directed to the SW, but there is
a faint front to the N and E. A plane of the sky velocity
was measured of ~750 km/sec.
1998/05/06 02:28 A small slower CME appears in C2 to the E apparently
originating from behind the limb. (this is not a halo)
1998/05/06 08:29 A very wide and fast (~1070 km/sec) CME appears in C2.
It appears to be mostly confined to the West limb. This CME was
associated with the X-Flare and enegertic particle event.
May 1-2 EVENT SUMMARY
From Shane Stezelberger (SOHO/LASCO)
LASCO detected two halo events associated with
recent on-disk solar activity:
1. A partial-halo CME, concentrated in the NE, was
in progress at 23:56 UT on 01 May. The plane-of-sky speed
was approx. 500 km/s. EIT detected several candidate on-disk
events, e.g. at 18:02 UT, 20:41 UT, 22:06 UT, and 23:15 UT. Further
ejections continued for several hours subsequently.
2. A bright partial-halo CME began at 14:06 UT, May 2,
concentrated in the NW. The measured speed was
approx. 750 km/s (west limb front).
From Don Michels (SOHO/LASCO)
X-class flare 980502 at 1340 UT, from region 8210 which is magnetically well
connected to Earth. LASCO CCD detectors were flooded
with proton hits, and the telemetry buffer was slowing down owing to the
large number of image features to be handled by the compression algorithms.
From Patrick S. McIntosh (NOAA/SEC)
MAJOR PROTON EVENT IN PROGRESS
CLASS-X FLARE REGION 8210 1340 UT
HIGH-ENERGY PROTONS ARRIVED IN LESS THAN 30 MIN
MAJOR MAGNETIC STORM IN PROGRESS
Region 8210 (S17 W17) produced a Class-X1 flare at approx. 1340 UT
980502 and high energy protons arrived in less than 40 minutes. The event
occurred near the rapidly developing delta configuration. The sunspots are now very
complex and showing clockwise rotation, including the delta-configuration. These are
classic properties of proton-flare sunspots.
From Mike Kaiser (WIND/WAVES)
Following the X1.1 flare was a relatively intense
interval of what we think is a moving type IV event -- from the ejecta
itself. This emission is seen from the top of the band (14 MHz) down
to ~8 Mhz and from about 14:05 - 15:50 UT. At lower frequencies,
there are two different episodes of type II-like emissions.
The first is in the 4-3 MHz range at about 14:15 to 14:45 UT. The
second episode is a bewildering complex of many narrow-band emissions
drifting downward from ~3 to 1 MHz in the 16:50 to 18:30 UT interval.
Starting mid-day on May 4, there is a weak fundamental-harmonic pair
drifting from ~55 kHz to ~35 kHz (fundamental). Although these are
very low frequencies, the in situ solar wind density is extremely
low right now (~1 cm^-3) so the shock is probably not too close to
April 29 EVENT SUMMARY
From Scott Paswaters (SOHO/LASCO)
LASCO/EIT observed a halo CME on 1998/04/29 from the same
AR that produced the halo CME on 1998/04/27. In LASCO data this
event has a very similar shape to that event 2 days ago,
although it appears to be slightly more centered on the Sun as
to be expected. The event began in EIT around 16:00 UT showing a coronal wave
in subsequent frames. The event appears in LASCO/C2 at 16:58
and is still in the C3 FOV. Measurements on the frames we have
received so far give a plane of the sky velocity to the NE of ~900 km/sec.
From Dave Speich (SEC/NOAA)
Active to minor storm conditions are predicted to occur 01-02 May in response to the
980429 halo event. Isolated periods of major storm are considered possible during the
30 Apr-02 May period.
From Murray Dryer
There was a strong Type IV (Type II hiding behind its skirts?), starting at 1707
UT on April 29 (continuing to the 30th) from a S18E20 flare at
1606-1638-1639..start, max, end of X-rays....M6.8/3B with a well-defined
halo CME, having plane-of-sky speed of 900 km/sec.
From Fred Ipavich (SOHO/Celias)
SOHO/PM detected a clean shock at 2115 UT on 1 May. The shock
travel time (~53 hours) is, I believe, the shortest we've seen on SoHO.
The shock/CME produced a very impressive Forbush Decrease.
From Patrick S. McIntosh
The magnetic storm expected from the X1 event of 29 April arrived late
on 01 May and is now of major proportions.