Noch ein M6,4. Kleiner Dienstags-Chat ?

[Lutz Schenk]

Hi Zusammen,

bin mal für ein Weilchen im Chat.

http://polarlicht.mainchat.de/

Dann gab es auch noch zwei "faint" Full-Halo's heute morgen aus 646:

UCMEO 93001 40713 1630/
40713 60054 81118 0001/ 360// 713// 20406
40713 60009 80023 44514 10646 1112/
99999

PLAIN

BT

LASCO & EIT observed a couple of at least partly Earth-directed
events on 2004/07/13, which showed up in the LASCO coronagraphs
FOV as rather faint 'full' Halo CMEs. This report refers to the
first of them. In short the second event will be reported.

The first event was first observed in C2 at 00:54 UT above the
NW Limb as a bright loop front with faint extensions to S. By
01:31 UT the faint extensions seem to cover the C2 occultor,
though due to their faintness, they are difficult to follow
after a couple of frames. The halo extensions are barely visible
in C3. During the evolution of the event in C2, at least two
parts can be distinguished: i) a bright ragged loop front, and
ii) a fainter and diffuse front to N and also ahead of the other
front. At 01:31 UT, bright material appears to N, below the
faint front previously mentioned, developing toward NNW. An
apparently twisted (and rather circular) structure develops
below the bright material. The circular structure seems to
surpass later, while still in C2, the bright material. By
05:30 UT more bright material appears above the NNW limb. By
09:08 UT, what I refer as the second event appears in C2 just
above the WNW Limb, developing much faster than the bright
material (see next report).

The mean plane-of-sky speed for the event as measured at the LE
of the ragged front [i)], at PA ~289, was ~406 km/sec (based on
C3 data).

The event was associated with complex solar activity reported
by GOES on the visible side of the solar disk, more precisely,
related to activity above the NOAA AR 0646. That AR produced
several C- and M-class X-ray flares during the day. For
completness, the list of the X-ray events reported at the time
of writing is given below:

Start Peak End Flare Location
00:09 00:17 00:23 M6.7 N14W45
05:21 05:33 05:40 C6.7 N14W49
06:26 06:33 06:48 C4.1 N14W51
07:10 07:14 07:19 C2.6 N14W50
08:40 08:48 08:55 M5.4 N14W51

Most likely, the X-ray event reported to start at 00:09 UT is
the one associated to the start of the C2 event. On the other
hand, EIT Fe XII images show a brightening above the AR mentioned
starting at 00:12 UT. A CME signature is seen traveling toward
NW afterward, originated on or nearby the AR. Likewise, an
intensity disturbance is seen traveling across the disk (wave).
Starting at 00:24, material (seen in absorption in EIT/Fe XII)
is ejected from nearby the AR apparently toward N and NE.

The complex event has therefore been determined as, at least,
partly Earth-directed.

Images and movies will shortly be made available at (for both,
the event reported in this message and what I referred as
the second event):

ftp://ares.nrl.navy.mil/pub/lasco/halo/20040713

Best wishes,
Guillermo Stenborg


+--------------------------------------------------+
Dr. Guillermo A. Stenborg
SOHO-LASCO Operations Scientist,
CUA, MC 682.3, 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
+--------------------------------------------------+


und noch einer:

UCMEO 93001 40713 1730/
40713 60908 91718 0001/ 360// 213// 20571
40713 60840 80855 45114 10646 1112/
99999

PLAIN

BT

LASCO & EIT observed a couple of at least partly Earth-directed
events on 2004/07/13, which showed up in the LASCO coronagraphs
FOV as rather faint 'full' Halo CMEs. This report refers to the
SECOND of them.

The second event was first observed in C2 at 09:08 UT just above
the WNW Limb, developing in the trailing material of previous
reported event. As for the other event, during its development
in C2, 2 parts are distinguishable: i) a bright ragged loop
front, and ii) a fainter and diffuse front to N and ahead of
the other front. By 10:30 UT the faint extensions seem to cover
the C2 occultor, though due to their faintness, they are
difficult to follow after a couple of frames. The halo extensions
are, like with previous event, barely visible in C3.

The mean plane-of-sky speed for the event as measured at the LE
of the ragged front [i)], at PA ~278, was ~571 km/sec (based on
C3 data).

In this case, the C2 event was most probably associated with
the M5.4 X-ray flare occurred above NOAA AR 0646 (by the time
at N14W51) between 08:40 - 08:55 UT with peak emission at
08:48 UT. EIT Fe XII running difference images show signatures of
the event between approximately 08:48 and 10:14 UT, showing
the brightening (flare) peaking at 08:48 UT. Moreover, like in
previous event, a large intensity disturbance traveling across
the disk mainly toward NE is evident (wave) and also toward NW
(CME signature). This event has therefore been determined as,
at least most likely, partly Earth-directed.

Images and movies will shortly be made available at (for both,
the event reported in this message and previous reported event):

ftp://ares.nrl.navy.mil/pub/lasco/halo/20040713

Best wishes,
Guillermo Stenborg

+--------------------------------------------------+
Dr. Guillermo A. Stenborg
SOHO-LASCO Operations Scientist,
CUA, MC 682.3, 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
+--------------------------------------------------+


Viele Grüße,

Lutz