1. MESSENGER MASCS M1 Flyby Preliminary Results

2. MASCS Flyby Trajectories Courtesy Killen et al. 2008 LPSC Abstract

3. Tailsweep H, Na spacecraft (S/C) time shown ~1 min S, Na H,O,O,Ca,K,Na S, Ca, K, Na MASCS at M1 Courtesy Killen et al. 2008 LPSC Abstract

4. Preliminary Results H, Na, and Ca observed S and K not observed First high spatial resolution observations of the Na tail emission First detection of the H tail emission First time H and Na observed in the tail simultaneously Ca detected in near-Mercury atmosphere Spatial asymmetries seen in the Na and H emission – confirms ground-based measurements of asymmetry Killen et al. collected ground-based observations of the Na emission from Kitt Peak’s McMath-Pierce Solar telescope during the flyby

5. Color Scale: 0 – 40 KRayleighs

6. Color Scale: 100 – 400 Rayleighs