SOHO/LASCO Halo CME 20211101

Halo Alert: halo-message.20211101

UCMEO 93001 11101 1800/
11101 60148 81042 0461/ 314// 333// 40639
11101 60057 80230 34529 12887 1112/
99999

PLAIN

SOHO/LASCO PARTIAL HALO CME November 01, 2021

C2 Start Time:     01:48 UT

C3 Start Time:        02:18 - 10:42 UT

Type of CME:
Asymmetric HALO CME — FRONTSIDE
pa1: 046      pa2: 314       Total Width: 268 degrees

Velocity Measurements:

C2    6 points    0639.0 km/sec @ PA 242
C3    9 points    0606.2 km/sec @ PA 242
Average through both fields:     0638.7 km/sec Acceleration: -8.90 m/sec^2.

COMMENT:       AIA 193 shows a long duration flare of AR 12887 at location [S29, W45]
                                            00:57-02:30 UT. The event produces a dimming in the West South
                                            West along with an EUV wave followed by a bright post loop arcade.


            STEREO Beacon Data - Data Gap: 00:00 - 03:38 UT
            COR2 A, shows a CME in progress from the South West.
            Preliminary time/height measure gives 0577.4 km/sec @ 251 degrees.

NOAA/GOES reports a M1.5 class X-ray flare of AR12887 00:57/01:45/02:10 UT.

There is increased SEP (Solar Energetic Particle) seen in the LASCO images.

Preliminary UCMEO velocity and position measurements are delivered first.
Images, movies, and time/height information for this event will be available at:

https://umbra.nascom.nasa.gov/lasco/observations/halo/2021/211101/

Best Regards,

--Kevin Schenk

BT

[Images from the original alert message are omitted here]