A Lander for Marco Polo

Transcription

1 A Lander for Marco Polo Hermann Boehnhardt MPI for Solar System Research Katlenburg-Lindau, Germany Lutz Richter DLR, Institute for Space Systems Bremen, Germany

2 The ROSETTA Lander PHILAE passive lander with anchoring single landing; 2π rotation, but no mobility 10 scientific instruments built & operated by European consortium and ESA

3 Why a MarcoPolo Lander? Unique in-situ science geology & morphology by imaging facies and surface structure by microscopy elemental, molecular, isotopic composition and mineralogy by various techniques (incl. organics & biological relevance) thermal properties by T sensors activity by volatile detector (TBD) seismic behavior by seismic sensor (TBD) mechanical & electrical properties (TBD) important aspect of lander usage is the development of general planetary surface exploration and of the respective robotic technology (sample return approach might be too complex, expensive or even impossible)

4 Why a MarcoPolo Lander? Complementary & context & combined science immediate ground-truth reference for orbiter mapping reference for sample return in-situ & immediate & uncontaminated local context & global context by in-situ analysis of more surface sites (similarity & diversity) wider surface area 3D context: surface & subsurface larger surface volume temporal behavior on surface diurnal & secular behavior scientific guidance of orbiter sampling analyze target site with lander first before sending the orbiter down to the surface seismic exploration during touch & go of orbiter (TBD) insights in body interior other (electric/mechanical) surface science (TBD)

5 Lander Requirements Scientific requirements unique and essential science suite of instrument for achievement of science goals of mission support of sample return mission (target site exploration) complementary science for orbiter and sample return mission Special technology requirements reusable for multiple landing (hopping) anchoring & release option sampling or handling support 2π surface & subsurface sampling Special mission requirements lander delivery targeted landing multiple landing lander surface exploration before orbiter sampling orbiter relay

6 A Lander Strawman Payload Imaging system Operations: descent, landing, on-surface, ascent Science goals: morphology & geology of landing site Additional goals: lander navigation Heritage: many (ROLIS, CIVA) Optical microscope (not in MarcoPolo proposal) Operations: on-surface Science goals: facies of surface to μm-scale Heritage: PHOENIX Comment: combination with imaging system might be possible Temperature Sensors Operations: on-surface Science goals: thermal properties, surface/subsurface T distribution Special aspect: time profiles (diurnal, secular) Heritage: ROSETTA

7 Electron Microscope EM or APXS Operations: on-surface Science goals: total elemental composition (EM, APXS), localized element distribution (EM), mineralogy (EM), microstructure - chondrules (EM) Special aspects: elements lighter than C not detectable (EM, APXS), lifetime of α particle emitter (APXS) Heritage: none (EM), MARS-PATHFINDER, MER, PHILAE, EXOMARS (APXS) Electron Microscope

8 Electron Microscope backscattered electron image optical image 5mm Al Mg Si Fe K Ti

9 Alpha Particle X Ray Spectrometer X ray spectrum backscattered α particles

10 Mößbauer spectrometer (not in Marco Polo proposal) Operations: on-surface Science goals: Fe solids mineralogy, Fe oxidation Heritage: MER Complementary: Raman spectrometer

11 Mass spectrometer & gas chromatograph Operations: on-surface Science goals: elemental+molecular+isotopic composition, organics Special aspect: biological relevance of material (chirality), D/H ratio of water, laser (instead of oven) for particle emission from solids Heritage: PHILAE, EXOMARS Mixed water amu mass spectorscopy Signal GC CalGas, 30 May 2002 Nobles gases Time gas chromatography

12 Lander Heritage PHILAE lander onboard ROSETTA (~100kg, landing on comet in Nov. 2014) positive aspects for MarcoPolo: passive landing on km-size body no contamination issue by engine exhaust multiple on-site sampling (2π annular sampling area) sub-surface sampling through drill suitable instrumentation high TRL level and replication of s/c and instrument HW space proven (to some extent and so far, final and crucial experience on landing is still pending) pending technology aspects for MarcoPolo: landing accuracy varies depending on release distance (and gravity field [and object activity comet only]) multiple landing not foreseen feedback loop for experience/knowledge transfer on small body landing may be too short (depends on MarcoPolo launch date)

13 Concept Selection for Suggested Landing Package A B C D Selected concepts for further analysis

14 Further Study Work: Basic Elements and Goals Science Strawman Definition Mission Analysis Thermal Control Structure & Mechanisms Primary Study Goals Establish a baseline design for the suggested landing package for concepts A and B Prelim. Analysis of Deployment / Landing Options Design Workshop (concurrent engineering approach for a preliminary spacecraft design) Study Elements GNC & Core Avionics Power & Electric s Propulsion Payload Define a science payload and its accomodation within the landing package Demonstrate the feasibility of the proposed concepts within the budgets and constraints of the MP main spacecraft and mission

15 Handling Support PLUTO system on PAW instrument carrier

16 Summary lander will make important scientific contributions to the Marco Polo mission: stand-alone & in-context lander will contribute enormously to the success of the desired sample return lander technology and instrumentation is available in Europe and can be enhanced to the needs of the MarcoPolo mission lander will add an acceptable complexity to Marco Polo with considerable benefits for the scientific success of the mission lander must be part of the Marco Polo mission