SOHO/LASCO Halo CME 20250830

Halo Alert: halo-message.20250830

UCMEO 93001 50831 2140/
50830 61948 80242 1221/ 121// 123// 41130
50830 61906 82015 11204 14204 1112/
99999

PLAIN

SOHO/LASCO HALO CME August 30, 2025

C2 Start Time:     19:48 UT

C3 Start Time:        20:30 - 02:42 UT

Type of CME:
Partial HALO CME — FRONTSIDE
pa1: 122      pa2: 121       Total Width: 360 degrees

Velocity Measurements:

C2    3 points    1287.4 km/sec @ PA 122
C3    11 points    1088.1 km/sec @ PA 122
Average through both fields:     1130.4 km/sec Acceleration: -45.40 m/sec^2.

COMMENT: SDO AIA 193A data shows a flare from a surfacing AR 14204 at location
    N04, E12] 19:06 - 20:15 UT LDE and noted as a M2.8 class X-ray.
    The region is adjacent to AR 14199 [N04, E04] and appears to be associated.
    The flare produces a large loop CME expanding to a full HALO CME. An
    EUV wave is seen propagating East along with a dimming seen in 193A.
    The long duration event finishes with post loop arcade.


     LASCO C2/C3 shows an asymetric full HALO CME over the East.

     STEREO Beacon Data
     COR2 A, shows a bright asymetric partial HALO CME over the East 19:53 - 22:23 UT.
     Preliminary time/height measure shows 5 points - 1287.7 km/sec @96 deg.

NOAA/GOES reports a M2.7 class X-ray flare of AR14199 19:11/20:02/20:41 UT
SolarSoft Latest_Events shows a M2.8 class X-ray flare 19:11/20:02/20:18 UT

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

https://umbra.nascom.nasa.gov/lasco/observations/halo/2025/250830/

Best Regards,

--Kevin Schenk

BT

[Images from the original alert message are omitted here]

________________________________________________
Soho-halo-alert mailing list
Soho-halo-alert@lists.nasa.gov

SOHO/LASCO C2 Diff	SOHO/LASCO C3 Diff	SDO AIA 195 angstrom

STEREO/COR2 BEHIND Diff	SDO AIA 195 angstrom Diff	STEREO/COR2 AHEAD Diff

SOHO/LASCO C2	SOHO/LASCO C3	AR14204