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HSWT#29, Florence February 28, 2005. DWE: Initial Results Michael Bird (Radiostronomisches Institut, Universität Bonn) And the DWE Team. DWE data: Huygens Mission. Channel B. f. Channel A. f. df/dt. df/dt. 6 hours. 3.67 hours. No power!. DWE from Earth: Geometry.
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HSWT#29, FlorenceFebruary 28, 2005 DWE: Initial Results Michael Bird (Radiostronomisches Institut, Universität Bonn) And the DWE Team
DWE data: Huygens Mission Channel B f Channel A f df/dt df/dt 6 hours 3.67 hours HSWT#29, Florence
No power! HSWT#29, Florence
DWE from Earth: Geometry • Huygens antenna pointed only ~30° from Earth • Better SNR than for Galileo Probe detection at Jupiter • Probe velocity projection in direction to Earth nearly antiparallel to projection in direction to Orbiter HSWT#29, Florence
GBT Parkes HSWT#29, Florence
Huygens Radio Tracking Net 10:18 UTC-GRT 12:30 UTC-GRT HSWT#29, Florence
GRT GBT Huygens! (~ -171 dBm) Flux density: 125 Jy HSWT#29, Florence
GBT Detection HSWT#29, Florence
Watching Huygens from JPL HSWT#29, Florence
Huygens Frequency: GBT + Parkes HSWT#29, Florence
Huygens Frequency: GBT + predicts HSWT#29, Florence
Huygens Frequency: Parkes + Predicts predicted impact HSWT#29, Florence
Parkes: Huygens Impact on Titan HSWT#29, Florence
Doppler Components GBT (1) Raw Doppler (2) Only Huygens Motion (3) Huygens Descent Velocity (4) Huygens Horizontal Velocity HSWT#29, Florence
Integrate wind velocity to obtain: DWE DISR Huygens Eastward Drift During Descent Difference HSWT#29, Florence
DWE: Preliminary Results • Zonal winds above boundary layer are PROGRADE • Low-velocity layer between 60-80 km • Stong positive/negative wind shear • ‘Unexpected’, but evident in some GCMs • Considerable turbulence above 100 km • Near surface winds are weak (~ 1-2 m/s) HSWT#29, Florence
Wind Shear and Stability HSWT#29, Florence
Richardson Number HSWT#29, Florence
Thermal Gradients HSWT#29, Florence