A dataset provided by the European Space Agency

URL ftp://npsa01.esac.esa.int/pub/mirror/CASSINI-HUYGENS/HASI/HP-SSA-HASI-2-3-4-MISSION-V1.1
DOI 10.5270/esa-jdccbuj
Abstract N/A
Description 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 Titan's 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 quasi-static 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 CDMU-A and CDMU-B). 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 ...
Instrument HASI
Temporal Coverage 2005-01-14T09:01:17Z/2005-01-14T12:10:20Z
Version V1.1
Mission Description The majority of the text in this file was extracted from the Cassini Mission Plan Document, D. Seal, 2003. [JPLD-5564] The Cassini spacecraft, including the Huygens Probe, was launched on 15 October 1997 using a Titan IV/B launch vehicle with Solid Rocket Motor Upgrade (SRMU) strap-ons and a Centaur upper stage. The spacecraft used a 6.7-year Venus-Venus-Earth-Jupiter Gravity Assist (VVEJGA) trajectory to Saturn, during which cruise observations were conducted to check out, calibrate, and maintain the instruments as well as to perform limited science. After Saturn Orbit Insertion (SOI) (1 July 2004), the Huygens Probe separated and, on the third encounter with Titan, entered the satellite's atmosphere to make in situ measurements during an approximately 150 minute descent (14 January 2005). The Orbiter continued a tour of the Saturn system until mid-2008 collecting data on the planet and its satellites, rings, and environment. The Cassini Orbiter (CO) was a three-axis stabilized spacecraft equipped with one high gain antenna (HGA) and two low gain antennas (LGAs), three Radioisotope Thermoelectric Generators (RTGs) for power, main engines, attitude thrusters, and reaction wheels. It carried twelve orbiter instruments designed to carry out 27 diverse science investigations. The Huygens Probe (HP) was equipped with six instruments designed to study the atmosphere and surface of Titan. It entered the upper atmosphere protected by a heat shield, then deployed parachutes to descend slowly to the surface from an altitude of about 200 km. The instruments, with acronym and Principal Investigator (PI) or Team Leader (TL), are summarized below: Instrument Acronym PI/TL ----------------------------------------------- ------------ Orbiter: Cassini Plasma Spectrometer CAPS Young Cosmic Dust Analyzer CDA Srama Composite Infrared Spectrometer CIRS Flasar Ion and Neutral Mass Spectrometer INMS Waite Imaging Science Subsystem ISS Por...
Date Published 2006-10-12T00:00:00Z
Publisher And Registrant European Space Agency
Credit Guidelines European Space Agency, 2006-10-12T00:00:00Z, HP-SSA-HASI-2-3-4-MISSION, V1.1. https://doi.org/10.5270/esa-jdccbuj