1. Review of Prominences in 304Å Lewis Fox 9/29/03

2. Outline Motivation for this talk: MOSES. What am I doing here? Pretty Pictures and Movies. Overview of some recent results. Some Open Questions Motivation MOSES - reprised

3. Motivation MOSES – Multi-Order Solar EUV Spectrograph A sounding rocket flight for June ‘04: –Primary Science Mission: the “He II Problem”. –Proof of Concept mission for Multi-Order Slitless Spectroscopy. –Narrow band operation near 304Å

4. What Am I Doing Here? AAS 2002 Meeting: Sara Martin Speaks –Charles talks to her about MOSES afterward, then tells me about the conversation. –Charles: “Sara Martin says we could use MOSES to study prominences and filaments.” –My response: “What’s a filament?”

5. What Am I Doing Here? Early September 2003: Sara Martin invites MSU faculty and students to the PROM meeting. –I mention the MOSES prominence/filament connection to Loren Acton. –A conversation ensues. Several emails are exchanged. Result: I’m standing up here instead of sitting down there.

6. Pretty Pictures

9. Pretty Movies

10. Overview of Recent Results Early indications were prominences in He II 304 are essentially the same as in H  –Led to multi-threaded isothermal strand model –Formation temperature? 80 kK vs. 30 kK. Recent results show some differences between the two: –He II from upper portion, H  from lower (Wang et. al.) –Can have He II prominence without H  emission (ibid.)

11. Overview of Recent Results Other general properties also differentiate them: –He II prominences frequently taller; ~3-4 thousand km. (Martin, 2002) –Frequently tens of thousands of km longer (ibid.) –Mass flows ~30 km/s ranging from 10 – 70 km/s (Wang, 1999) as compared to 5 – 20 km/s in H  (Zirker et. al., 1998). –Barbs do not usually coincide, but they obey the same chirality rules. (Wang, 2001). –He II shows the outer part, H  the inner part.

12. Some Open Questions It has been suggested that barbs terminate in regions of minority polarity (Wang, 2001, Martin and Echols, 1994). –This has been observed in H . –But not yet shown in He II due to resolution of EIT. Counterstreaming barb flows: –Have they been observed in He II?

13. Some Open Questions Activated Intervals: –Are they observed in He II? –What is their connection to eruption? EIT data has correlated prominence eruption to CME’s in some cases (c.f. Delannée et. al. 2000) –How strong is the correlation? –What other factors play a role? What are the dynamics of prominence lift-off in He II?

14. Motivation MOSES (reprised) Instrument Parameters –0.6”/pixel –8.5’x17’ FOV –20 mÅ spectral resolution –Narrow 304 band excludes all lines except Si XI 303.3 Å and He II 303.8 Å MOSES will be capable of fast (10 s cadence), simultaneous, imaging spectroscopy.

15. How?

16. Ill-posed inversion: –Will we be able to extract meaningful information in this way? Current trial inversions can compute doppler shifts to 7 mÅ. Forward modeling is a viable option. –Robust code exists.

17. This has Promise… Should have the spatial, spectral, and temporal resolution to address many of the questions raised. All I want for Christmas is an Orbiter. –5 minutes is not a lot of temporal coverage. Coordination with other observatories a must –Large FOV helps. –Let’s hope for something exciting…

18. Thanks To: Dr. Sara Martin for allowing me to take up this time at her meeting. Dr. Loren Acton for arranging it (and encouraging it). Dr. Charles Kankelborg for MOSES, without which I’d be doing High-energy cosmic rays or General Relativity. Dr. Piet Martens for advice and encouragement.