HP-SSA-HASI-2-3-4-MISSION

Data Set Overview THe Huygens Atmospheric Instrument is one of the six experiment onboard the Huygens probe. HASI is a muultisensor package designed to measure the physical quantities characterizing Titans atmosphere during entry and descent phase and at the surface. Science Objectives and Observational Strategy: HASI science objectives for the Huygens missione are to: determine the atmospheric density, pressure and temperature profiles Determine the atmospheric electric conductivity and charge carrier profiles Investigate ionisation processes Survey of wave elelctric fields, lightining and analyse the quasistatic electric fields leading to storm formation Detect acoustic noise due to turbulence or storm Characterise the roughness, mechanical and electric properties of the surface material, whatever its phase, solid or liquid These objectives are addressed at one location and time, but a very high resolution ground thruth for the calibration of remote sensing observations. The observational strategy for the Huygens probe is fixed by a programmed sequence, HASI observations, mode switching are organized in a timeline triggered by events (e.g. T0 detection), time and altitude information provided by Huygens CDMS via the DDBL (Data Distribution Broadcast Line). Parameters HASI S/W provides two independent telemetry queues: one dedicated to each Huygens Command and Data Management Unit (CDMU). HASI handles TM packets queues by the internal operating system, that allocate dynamically the memory for the packets. The memory remains allocated until the tM packet is discarded from the queue (TM queue capability of about 130 packets). Few seconds (about 132 s) after HASI power ON HASI telemetry starts (both on CDMUA and CDMUB). Acquired data are transmitted redundant on both CDMUs (with the exception for PWA science data, same packet content is transmitted on both CDMU TM line, but o truncated!, Please see actual data [truncated!, Please see actual data for full text]