Watch 1.3 für 02./03.09.2005

[Lutz Schenk]

Hallo Zusammen,

wieder mal hält uns die Sonne auf Trab...

Die ACE-Daten zeigen zwar den Schock, aber noch kein deutliches magnetic cloud feature.

http://www.sec.noaa.gov/ace/MAG_6h.html
http://www.sec.noaa.gov/ace/EPAM_24h.html
http://www.sec.noaa.gov/ace/MAG_SWEPAM_6h.html
(verfallen)

Daher jetzt dieser Watch nach 1.3 der Warnkriterien. Da die Schockbedingungen nicht deutlich gegeben sind, ist dieser erst mal vorsichtig.
http://www.sam-europe.de/warnindex.html

Das EPAM zeigte gar ncht mal so ein deutliche Rampe.
Ob da überhaupt eine Blase nachkommt scheint mir unsicher.

Sollte das Bz schön südlich bleiben, könnte es durchaus bunten Himmel geben.

Viele Grüße,

Lutz

Hier noch die Halo-CME-Mails zu dem C2-Flare-Komplex vom 31.08.

UCMEO 93001 50901 1455/
50831 61130 81942 0001/ 360// 113// 20860
50831 61026 81251 41313 10803 1112/
99999

PLAIN

BT


This is the report corresponding to the third event mentioned in my
previous Alert, i.e., of the Faint Full Halo Event first seen in LASCO/C2
on 2005/08/31 at 11:30 UT on the W Limb. A brief description of the
event follows:

A small brightening just appearing above the W Limb is first seen in
C2 at 11:30 UT, developing as a bright loop front. It is followed
(apparently about one hour later) by a fainter and diffuse expanding
loop front with faint extensions on E. The C2 occulting disk appears
fully covered by 13:31 UT. The "halo" looks rather flat over the poles,
and elongated toward W and E. The event is first seen in C3 above the
W Limb at 12:42 UT. The C3 occulting disk seems to be fully surrounded
by 12:42 UT. The event fades throughout C3. The mean plane-of-sky speed
of the outermost edge of the event on W (PA 285) was ~ 860 km/sec.

GOES reported a long duration C2.0 X-ray flare on NOAA AR 10803 (N13W13)
between 10:26 - 12:51 UT with peak emission at 11:51 UT. EIT 195 images
show a brightening on AR 10803 starting at 10:36 UT all along the
magnetic inversion line (extending E-W) followed by a dimming region
mainly to W and NW of the AR. Post flare loops.

In summary, the event has therefore been determined as a faint Full Halo
Event, frontsided, associated to a C-class X-ray event on NOAA AR 10803.

LASCO movies and images including also the 2 events reported in my
previous Alert will shortly be made available at:

ftp://ares.nrl.navy.mil/pub/lasco/halo/20050831



Best wishes,
Guillermo Stenborg


+--------------------------------------------------+
Dr. Guillermo A. Stenborg
SOHO-LASCO Operations Scientist,
CUA, MC 612.5, Bldg 26, Rm 001, F: +1-301-286-0264
NASA Goddard Space Flight Center,
Greenbelt, MD 20771. P: +1-301-286-2941

e-mail: stenborg@kreutz.nascom.nasa.gov
+--------------------------------------------------+



UCMEO 93001 50831 2045/
50831 60731 91418 3303/ 140// 613// 20445
50831 ///// ///// ///// ///// ///2/
99999

PLAIN

BT


LASCO/EIT observed three apparently distinct events on 2005/08/31 (by the
time of writing):

1) a very faint expanding loop front mainly developing toward NE, first
seen in C2 at 07:31 UT as a very faint and diffuse front above the NE
Limb (hereafter Event #1). By 09:06 UT, the angular span of the front
in C2 seems to cover from the ESE Limb up up NW Limb (clockwise), though
in NW is too faint to define its edge. It is first seen in C3 above the
NE Limb at 08:42 UT. Note that by 07:31 UT, a diffuse and rather
elongated front is also seen in C2 on SE.

2) another diffuse front (a little brighter than the previous one) shows
up later, more precisely at 10:06 UT, also above the NE Limb (hereafter
Event #2). By 11:30 UT, the event seems to span in C2 from ESE well up
to the NW limb (clockwise). It is first clearly seen in C3 above the NE
Limb at 10:42 UT.

3) a bright loop front that will apparently develop as a full
(frontsided) halo event (rather flat over the poles, elongated toward
W and E), just appearing in C2 above the W Limb at 11:30 UT. As SOHO
entered in a telemetry keyhole, we are actually in a telemetry DSN data
gap and therefore still waiting for the images to analyze its evolution
(last C2 image available taken at 14:30 UT, the event already by the end
of the C2 FOV). This event is associated to a long duration C2.0 X-ray
flare on NOAA AR 10803 (N13W13) between 10:26 - 12:51 UT with peak
emission at 11:51 UT. The corresponding report will be delivered on
thursday (09/01) morning (US eastern time), hoping the gap had been
filled by the time.

As for the events #1 and #2, they seem to coalesce in the C3 FOV by
12:18 UT (at about 11 solar radii), either because the second event
is faster or the first one becomes too faint to be distinguished.
The main plane-of-sky speed of Event #1 at PA 35 was ~ 385 km/sec
(last frame used: 10:42 UT; LE at ~ 9 solar radii). For the Event #2
the mean plane-of sky speed at PA 40 was ~ 445 km/sec (last frame used:
13:42 UT; LE at ~ 12.5 solar radii).

GOES reported no significant activity by the time prior to the first
appearance in C2 of events #1 and #2, except for a B3.2 X-ray flare on
NOAA AR 10806 (S17E32) between 09:52 - 10:08 UT with peak emission at
10:02 UT.

EIT 195 images show: i) a small ejection starting at 06:12 UT, on the
southern hemisphere close to the central meridian (far west of AR 10806),
just on the border of the southern coronal hole, developing toward SE,
ii) a dimming region just on SE of AR 10806 starting at 10:00 UT, i.e.,
during the time of the B3.2 X-ray flare, and iii) a brightening on
AR 10803 starting at 10:36 UT (but this is topic for the next report).

In summary, based on its appearance on C3, the events #1 and #2 considered
together could be classified as a faint and complex Partial (at least)
Halo Event. Though the timing of the EIT events seem to correlate with
the Events #1 and #2, the corresponding spatial location on the disk
doesn't. Therefore, it is hard to be sure about the source of Events #1
and #2.

LASCO movies and images including the 3 events will be made available by
thursday (09/01) at:

ftp://ares.nrl.navy.mil/pub/lasco/halo/20050831


Best wishes,
Guillermo Stenborg


+--------------------------------------------------+
Dr. Guillermo A. Stenborg
SOHO-LASCO Operations Scientist,
CUA, MC 612.5, Bldg 26, Rm 001, F: +1-301-286-0264
NASA Goddard Space Flight Center,
Greenbelt, MD 20771. P: +1-301-286-2941

e-mail: stenborg@kreutz.nascom.nasa.gov
+--------------------------------------------------+