Note on tracking Sun-Earth connection event ICME Event: 2009/01/25 Observer: Taylor Cox on 2018/11/27 1. ICME 1.1. Catalog # Identified in ICME catalogs: Richardson & Cain List RC catalog Disturbance start time: 2009/01/25 22:24 UT Ejecta Start time: 2009/01/26 10:00 UT Ejecta End time: 2009/01/26 15:00 UT dv = 50 km/s, v = 337.1 km/s, vmax= 388.1 km/s MC index: Dst: -29 Suggested source CME: N/A V_transit: 360 km/s 1.2. Comments Overall ICME quality index: # ICME signatures: Bmax: 110.8 nT Bz rotation Others ICME signature: Peculiar behavior: density and temperature data is lost within the ejecta Disturbance time 330 km/s -> search window 127 hrs -> 2009/01/15 13:00 UT 2. CME 2.1.A. Candidate A A.1. LASCO: #CME 2009/01/20 partial halo Full day outflow from CME late the day before. A.2. STEREO: STEREO observations show this outflow is directed away from the Earth, and as such would not be the source of the ICME A.3. AIA & GOES: flare magnitudes from goes and AR region data/descriptors from AIA/EIT A.4. Comments: Due to STEREO observations, this would not be a suitable candidate to produce this ICME 2.1.B. Candidate B. B.1. LASCO: CME 2009/01/20 09:00 UT, CME off of lower right of solar disk This quick CME may expand to the point where it could be Earth-Affecting B.2. STEREO: STEREO A STEREO A seems to show this CME as a halo, and one where it airs on the side away from the earth. STEREO B STEREO B shows the CME Earthward easily B.3. AIA & GOES: flare magnitudes from goes and AR region data/descriptors from AIA/EIT B.4. Comments: These observations do not completely rule out this CME, but the STEREO A observations seem to suggest that this CME would not be the cause of this ICME. 2.1.c. Candidate C. C.1. LASCO: CME 2009/01/21 20:30 UT, Right of Solar Disk C.2. STEREO: STEREO A is faint all around through the day on 01/22, when the even would be most visible, but some movement alludes to the Earthward direction as stronger possibility than away from Earth. STEREO B provides clear imaging of a CME in the Earthward direction. C.3. AIA & GOES: C.4. Comments: This event is hard to detect in STEREO A, but still seems to have enough signs to be reasonably considered Earthward. The remaining issue with this CME is that it is potentially too close to the time of ICME detection. given that this event starts at the night of 01/21, and this event is first detected the night of 01/25, it is a shorter time frame than expected significantly, but not entirely impossible. 2.2 Decided Source The most likely solar source is Candidate C. 3. Other Comments N/A 4. Summary SW index 2 Source index 3 Overall index 3 This was the process used to identify a region that may have produced solar activity to generate this ICME.