| dc.description | The work was presented a s a poster on the Monday of the meeting. There was a reasonable number of visitors to the poster and some useful discussion.
Most of the discussion of this event took place in a session on Tuesday, with two oral presentations. I was a co-author on one of them. Both of them referred to my poster, but of course since it was already gone, this did not help much. I had fruitful discussions with the main authors of both papers. Howard Singer I knew from before and had worked a bit on this with. Bill Denig I had never met and he pointed out some useful information. I will work with Howard in the near future on an article about the event and hope to also follow up with Bill.
At the meeting I did not have much time to interact with my main co-authors on this study, who are Chris Russell and Vassilis Angelopoulos of UCLA, both prominent and very busy scientists. Since in any case airfare was lower doing it that way (and covering other expenses form other funds) I came back from San Francisco via Los Angelesand had two working days at UCLA with Chris Russell. This way the groundwork for a basic change in our approach to the event by refocusing on electric fields. We had been trying to publish a general description of the event in prominent journals through the latter part of 2010 and not having much success in getting editors to send out for review (please note that this does not reflect quality but a subjective judgment by the editor on this wide significance. The refocus allowed us to submit to the letters section of Annales Geophysicae and we have submitted there and had the editor send out for review (which we await).
The feeling was reinforced at the meeting that this is a very important event to study. I also attended the THEMIS team meeting at Berkeley and made a brief (and in my opinion not very good) presentation on the event. Luckily, Howard singer made a much better presentation after mine which stimulated discussion, including questions for me. The high degree of interest means at this will be discussed at the next THEMIS team meeting in March. Howard is working on an article on more general
aspects and I will contribute that and we will see if that ends up being just one article, or possibly two with me being lead author on one that emphasizes ground magnetic perturbations. | en |
| dc.description.abstract | On April 5, 2010 around 09 UT, the NOAA Geosynchronous Operational Environmental Satellites (GOES) observed a large reconfiguration of the magnetospheric magnetic field in the midnight to dawn local time sector. Specifically, near midnight, the GOES-11 Hp (north-south) magnetic field increased by approximately 100 nT in 15 minutes. This is one of the largest dipolarizations of Earth:s field ever observed by GOES. At the same time, there were large increases in the flux of energetic electrons and protons and large ground magnetic perturbations. While the auroral electrojet index (AL) was extreme, being less than -2000 nT during this event, the preliminary, real-time Dst storm index was only on the order of -30 nT during the event (although it reached somewhat more intense values during the following day). The Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE) monitored currents at low altitude during this event, and these observations can be used to place the localized measurements at geosynchronous orbit in a global context. Additional measurements were made by the Time History of Events and Macroscale Interactions during Substorms (THEMIS) spacecraft just tailward of the GOES satellites. Minutes after the initiation of this intense substorm, at 0948 UT, Galaxy 15, located at geosynchronous orbit, just a few degrees away from GOES-11, suffered a serious anomaly and to date, contact has not been restored. At the time, it was reported that this anomaly was likely related to the solar generated event; however, the anomaly is still under investigation. The purpose of this presentation is not to evaluate the anomaly, but rather to describe the large response of the magnetosphere and ionosphere system to the solar and solar wind conditions that caused this extremely large substorm. | en |
