PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM LABEL_REVISION_NOTE = "2004-09-23 KW: Initial draft. 2005-12-09 AC: Orbiter Information Updated Added Inst_host for lander References TBD 2006-01-10 AC: Removed special characters 2006-02-15 PG: Added Inst_host for lander 2007-01-26 MB: 70 char line length 2007-08-14 MB: remove not ascii symbols 2008-02-02 Maud Barthelemy 2008-04-11 JL Vazquez, SA 2008-05-09, MB 2010-02-15, MB 2011-06-07, MB, editorial 2012-06-06, M. Barthelemy after AST2 review; 2017-04-26, M. Barthelemy missing reference and Lander updates. 2017-09-27, Maud Barthelemy, Ground Station Network updates 2017-11-17 Maud Barthelemy typo corrections 2018-07-17 Maud Barthelemy typo corrections 2018-08-30 DF: shall heve remained -> remained" OBJECT = INSTRUMENT_HOST INSTRUMENT_HOST_ID = "RL" OBJECT = INSTRUMENT_HOST_INFORMATION INSTRUMENT_HOST_NAME = "ROSETTA-LANDER" INSTRUMENT_HOST_TYPE = "SPACECRAFT" INSTRUMENT_HOST_DESC = " Lander overview ============================================= The Philae Lander was a box-type unit with the dimensions of 850 x 850 x 640 mm3. On the comet, it rested on a tripod called Landing Gear, with a diameter of 2.6 m and was supposed to be fixed to the comet's surface by harpoons. Philae was composed of three different parts, corresponding to its structural design: 1) Internal compartment: This compartment hosted almost all subsystems and most of the experiment units. It provided a temperature controlled environment for all electronics and was built by the structural elements of an Instrument platform and so called Pi-plates. It was surrounded by Multilayer Insulation built of 2 tents to achieve the required insulation at a low power environment on the comet at 3 AU distance from Sun. 2) Solar Hood: The solar hood was built around the internal compartment and its MLI tents, the shape followed the overall Lander shape. It hosted the solar arrays of the Lander composed by 6 different panels. In addition two absorber foils were mounted on the solar hood lid. These foils were built by thin copper foils with an external TINOX surface, high absorptivity and low emissivity, used to collect solar irradiation and transform it into heat radiated into the internal compartment. The solar hood also carried the camera system of the Lander, with one camera head on each panel, thus providing a 360 degrees panoramic view. 3) Baseplate / Balcony: The baseplate was the central structural plate carrying the solar hood with the internal compartment underneath and providing at one end a special area called balcony. This area hosted all experiments or parts of them, especially the sensors, which required direct access to the comet environment and the comet surface. The baseplate was also the interface panel to the Landing Gear. In addition the baseplate hosted the Push plate, which was the interface to the Orbiter during the 10 years cruise from Launch to the Comet. The Lander mass was around 100 kg. In addition three units of the Lander system were mounted on the Orbiter, and remained there after Lander separation for the comet. These units provided the interfaces to the Orbiter: electrical and data (ESS) and mechanical (MSS). The third system was a TxRx system used to keep contact to the Lander during its operational phase on the comet. Lander Mission Requirements and Constraints ============================================= The Lander was designed to fullfill the mission requirements given as: - survive the 10 years cruise phase with long hibernation phases under autonomous thermal control powered by the Orbiter, - land safely on the comet, - provide a scientific phase after landing at 3 AU distance from Sun with online data transmission, - provide a long term mission capability observing the comet on its way from 3 AU to the Sun Lander Platform Definition ============================================= The Lander platform was built by three major subsystems, required to operate the Lander throughout the mission: - a Power subsystem (PSS) composed of a Battery system with a Primary Battery and a Secondary Battery, the later refilled by a Solar array generator, and the required electronics to distribute and control the power flow inside the Lander, - a Central Data Management System (CDMS), composed by two hot redundant computers, controlling all activities on the Lander, especially on the comet in an autonomous manner, - a Thermal Control System, composed by a 2-tent MultiLayerInsulation supported by two absorber foils and an electrical heater system. Additional independant heater systems were used during the cruise phase, especially when the Lander was in hibernation, and on the comet, when the Lander run out of power and changed into a so called Wake-up mode, to provide a thermal environment in the Internal compartment as required to switch-on the Lander electronics. Subsystem Definition ============================================= In addition to the already described platform units PSS, CDMS and TCS and the On-Orbiter units ESS, MSS and ESS-TxRx, a set of subsystems was installed on the Lander. The Active Descent System ADS provided a 1-axis thruster system used at touch-down to support the landing and prevent a rebounding until the harpoons are shot. An Anchoring system, built by two redundant harpoons, was used to fix the Lander to the comet's surface after landing and provide the required counter-force during drilling. A Flywheel providing a 1-axis momentum wheel used to stabilize the Lander's descent to the comet. The Landing gear provided the necessary interface between the Lander and the comet and supported Lander science operations by a rotation and tilting capability. The structure subsystem provided the required structural elements to built up the Lander. A TxRx system was installed to provide access to the Lander and enable data retrieval during its mission phase on the comet. Lander Reference Frame ============================================= The Lander reference frame was defined as follows: +Z-axis was perpendicular to the baseplate, generally pointing away from the comet towards space, during cruise parallel to the Orbiter +Z-axis, +X-axis was generally parallel to the comet surface, pointing opposite of the Lander's balcony, into the direction of Lander separation from the Orbiter, during cruise into Orbiter -X direction, +Y-axis completed the right-handed frame. The frame origin was located on the upper surface of the balcony (Z = 0), in the middle of the balcony (Y = 0), at the outer end (X = 0). Lander Operating Modes ============================================= The Lander was operated in the following modes: Hibernation Mode: This mode was defined as: Lander attached to the Orbiter, Orbiter LCL 5A or 5B ON, Lander Hibernation heater ON (dissipation > 12W at 28V), no power on the Lander Primary Bus In this mode the Lander was non-operational but under thermal control with a hibernation temperature inside the internal compartment above minus 55 degC at the reference point. Wake-up Mode: This mode was applied on the comet, substituting the Hibernation Mode. The PSS wake-up thermostats were closed, because the temperature inside the internal compartment was below minus 53 degC. In this mode the Lander was non-operational, the Lander operational electronics were disconnected from the Primary Bus and the wake-up heaters were connected to the Primary Bus. In this mode NO thermal control was possible, since the wake-up heaters would only dissipate, if the Primary Bus was powered, which required Sun irradiation on the comet to operate the solar arrays. Without dissipation the compartment temperature would drop until the comet environmental temperature. When the Lander was still attached to the Orbiter and powered from the Orbiter-LCL 15A/B, an additional heater set would also dissipate. Power Enough Mode: This mode followed the Wake-up mode, the Lander Primary Bus was powered, but the voltage was still below 18.5V, which corresponded to a non-sufficient power situation. The available power was not lost, since special Power Enough loads were used to dissipate and heat the internal compartment. Stand-by Mode: The Lander was operational, since the Lander basic operational electronics (PCU, CDMS and one TCU) were connected to the Primary Bus and powered. In this mode thermal control would be performed from the dissipation of the activated units. If the temperature of the internal compartment dropped below the TCU set-points, the respective TCU heaters would also dissipate. Operational Modes: These modes defined Lander operation of Experiments. APXS: No activity during SDL and FSS. CIVA: CIVA-P mode Orbiter imaging : Imaging of the Orbiter after delivery with camera 1 & 6. CIVA-P mode Agilkia Landing site : Imaging of the Landing site Agilkia just after touch-down Panorama with all 7 camera but only half of image received. CIVA-P mode Abydos location : Imaging of the Abydos after touch-down and move on the comet Panorama with all 7 cameras. CONSERT: CONSERT Tuning mode: Instrument Switch ON and tuning of CONSERT Lander & Orbiter clocks. CONSERT Sounding during descent (SDL) mode: CONSERT Lander emission and reception by CONSERT Orbiter. Active during the whole descent and stop during the touch down window (CONSERT remaining active during this window but not sounding (RF emission) for no interference with other instruments at time of Landing. Lander and Orbiter in visibility during all this period as CONSERT main objective was to monitor the Lander descent trajectory. CONSERT Sounding after Landing mode: CONSERT Lander emission and reception by CONSERT Orbiter. Lander and Orbiter in occultation permitting the sounding of the comet structure. COSAC: COSAC Taping station test and sniff mode at Agilkia: Evaluation of the COSAC taping station position and disengage of the possible taping station of an SD2 Carousel Oven (previous to any SD2 Carousel movement). COSAC Abydos sniff mode: Analysis of the molecules present at the external entry of the COSAS Mass Spectrometer done in Agilkia just after landing and later on Abydos site. MUPUS: MUPUS Anchor mode: Measurement of the acceleration sensors ANC-M inside the harpoons during anchoring. Measurements of the temperature sensors ANC-T inside the harpoons. MUPUS MAPPER mode: Calibration of the Thermal Mapper during descent. Two sub-mode to MAPPER mode TM blackbody sub-mode: Calibration of the Thermal Mapper with blackbody in the TM field of view (during descent). Infinite TEM sub-mode: Calibration of the Thermal Mapper with deep space in TM FOV (during descent) MUPUS TEM mode: Passive Thermal Measurement Mode. MUPUS LONGTERM (-> MAPPER) mode: Thermal Mapper longterm measurement after landing and during one comet rotation. MUPUS PENEL deployment mode: Penetrator deployment. MUPUS HAMMER mode: Penetrator insertion to ground by hammering. PTOLEMY: PTOLEMY Sniff and CASE mode: Analyse of the molecules present at the external entry of PTOLEMY Mass Spectrometer. PTOLEMY Agilkia sniff mode and tapping station test: Analyse of the molecules present at the external entry of PTOLEMY Mass Spectrometer done in Agilkia just after landing. Evaluation of the PTOLEMY taping station position and disengage of the possible taping station of an SD2 Carousel Oven (previous to any SD2 Carousel movement). PTOLEMY Abydos sniff mode: Analyse of the molecules present at the external entry of PTOLEMY Mass Spectrometer done in Abydos site. PTOLEMY Oven mass spectrum analysis: Analyse of the molecules present in the Oven by PTOLEMY Mass Spectrometer done in Abydos site. ROLIS: ROLIS DIT mode: ROLIS imaging during descent Agilkia touch down location in the field of view. ROLIS DIS mode: ROLIS imaging during descent once landed. ROLIS CUC mode: ROLIS imaging once on COMET in Abydos site during night period with illumination by LED sources (blue, green dark, red, IR) Images of Abydos site. ROMAP: ROMAP Slow Mode: Magnetometer in Slow mode (1Hz sampling 512 octet / mn). ROMAP Fast Mode: Magnetometer in Fast mode (916 octet / mn). ROMAP Surface Mode SPM: Magnetometer and channeltron after Touch Down from Noon to Day/Night transition. SD2: SD2 Drill downward and upward for COSAC: Carousel movements to zero position Drill roto-translations downward and Sampling at 560 mm, translation upward to 0mm, sample in Oven#17(SD2 count, HTO) delivered to COSAC. SD2 Carousel movements: Carousel movement for PTOLEMY with rotation to 0 arcmin. SESAME: SESAME CASSE mode: Measurements executed to register the vibration environment generated by the Philae flywheel, intra-foot Soundings and inter-foot Soundings, touchdown impact, the cometary vibration background and any particles possibly dropping on the sole covers. SESAME PP Passive Mode : Measurements conducted in order to determine the electromagnetic environment close to the orbiter. SESAME PP Active Mode : PP calibrations, determine the permittivity of the comet surface material, monitor variations in the local plasma environment. SESAME DIM mode: DIM conducted to measure the particle environment." END_OBJECT = INSTRUMENT_HOST_INFORMATION OBJECT = INSTRUMENT_HOST_REFERENCE_INFO REFERENCE_KEY_ID = "BIBRINGETAL2007B" END_OBJECT = INSTRUMENT_HOST_REFERENCE_INFO END_OBJECT = INSTRUMENT_HOST END