10/08/2012 05:00:00 UTC
- This is a varSITI campaign event
- A good ICME, strong CME source, however, "stealth" surface signature (J. Zhang)
- A good example of "stealth" CME: bright CME, but no or very weak surface signature (in terms of no flare, dimming, filament eruption etc)
- This event has a very difficult to distinguish source region, if you look very closely at S22 W38 just before 00:00 UT on the 10/05 it is possible to see a very small disturbance on the Sun, especially in 304 Angstroms. (Hess)
- M. Temmer: clear on-disk signatures - movie from SDO - are visible. It is a "silent" CME, hard to catch for space weather forecasters, but not a "stealth" in sense of no solar surface signatures at all.
http://sdowww.lmsal.com/sdomedia/SunInTime/2012/10/04/daily_211-193-171.mov [October 4, 15UT, central south]
I put some images showing clear coronal restructuring and some discussion points under> http://www.uni-graz.at/~temmerma/download/varsiti/
- C. Moestl: looking at the whole October 4 SDO movie, there are also two other minor eruptions which I find very hard to distinguish from the 15 UT one (1. 7 UT, slightly west of disk center; 2. 0930 UT, south-east quadrant)
- timing - evolution from SDO FoV to coronagraph - is an issue and needs to be looked at in detail
- these eruptions are also visible in the SWAP data (http://proba2.oma.be/), including another minor one at 14h UT in the south-east quadrant (A. Devos)
- Discussion in USTC-China ISEST Workshop on April 19, 2014
- Inferred from GCS model based on STEREO/A, STEREO/B and SOHO coronagraphs, longitude W11 deg, latitude S20 degree
- Around this position, there was a minor activity from 14 to 15 UT on Oct. 14 seen in SDO AIA 193 images. The activity appeared as a weak dimming followed by a diffuse brightening.
- In EUVI-A 195, from 22 UT on Oct. 14, there was a very faint eruption above the south-east limb. This beyond-limb faint eruption is consistent with the heliospheric position of W11S20.
- The CME continued to accelerate to about 10 Rs with a peak speed of 800 km/s at 06 UT, Oct. 15.
- If the eruption started at 14 UT, Oct. 14, it took a long time (10 hrs) for the eruption to reach the COR1 FOV. It indicates that the eruption has a long-lasting low-speed low-acceleration phase
At Earth it produced a small storm, Dst=-105. Electron acceleration in the radiation belt has been measured by the Van Allen Probes and studied by Reeves, et al (2013), Thorne et al. (2013, and Kurita et al. (2016). studied by Reeves, G.D. et al (2013). [Added by D. Webb]
Jmaps from STEREO A and B along the CME leading edge position angle
Heliospheric Imager Data
AIA 304 Running Difference Movie
AIA 195 Running Difference Movie
STEREO EUVIA 304
PROBA2 SWAP 174
PROBA2 SWAP 174 Difference Movie
- Reeves, G. D., et al. (2013), Electron acceleration in the heart of the Van Allen radiation belts, Science, 341(6149), 991–994, doi:10.1126/science.1237743.
- Thorne, R. M., et al. (2013), Rapid acceleration of relativistic radiation belt electrons by magnetospheric chorus, Nature, 504, 411–414, doi:10.1038/nature12889.
- Kurita, S., Y. Miyoshi, J. B. Blake, G. D. Reeves, and C. A. Kletzing (2016), Relativistic electron microbursts and variations in trapped MeV electron fluxes during the 8–9 October 2012 storm: SAMPEX and Van Allen Probes observations, Geophys. Res. Lett., 43, 3017–3025, doi:10.1002/2016GL068260.
- Webb, D., N. Nitta: 2017, Study on Understanding Problem Forecasts of ISEST Campaign Flare-CME Events, Solar Phys., submitted.
- Nitta, N. V., T. Mulligan: 2017, Earth-Affecting Coronal Mass Ejections Without Obvious Low Coronal Signatures, Solar Phys., submitted.
- Marubashi, K., K.-S. Cho, H. Ishibashi: 2017, Interplanetary Magnetic Flux Rope as Agent Connecting Solar Eruptions and Geomagnetic Activities, Solar Phys., submitted.