1. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK Penetrators for TSSM MSSL/UCL UK Rob Gowen on behalf of UK Penetrator Consortium TSSM Meeting - Monrovia, Jun 02 2008

2. MSSL/UCL UKMicro-Penetrators Basics : Low mass [~5Kg] Very tough [~ 200-500 m/s, impact ~10-50kgee] Perform science from below surface [~0.5-few m] 5 kg 2 kg payload Payload (2kg)Science Capability Micro seismometerssub-surface ocean, inner body structure (astrobiology, geophysics) Chemistry package (mass spect.)organics and inorganics (astrobiology) Soil/environment package (accelerometers, thermometer, dielectric constant, radiation monitor, magnetometer, pH, Redox) soil mechanical properties, thermal & electrical properties (astrobiology /geophysics) Mineralogy/astrobiology cameraSoil properties/astrobiology Descent cameraImpact site context & PR

3. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK Impact Trial 19-21 May 2008  Full-scale trial  3 Penetrators, ~0.6m long, ~13kg, Aluminum  300m/s impact velocity  Normal Incidence  Dry sand target 0.56m

4. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK Impact trial - Contributors

5. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK Impact trial – Payload Radiation sensor Magnetometers Batteries Mass spectrometer Micro-seismometers Drill assembly Accelerometers Power Interconnection Processing Accelerometers, Thermometer Batteries,Data logger

6. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK Impact Trial Objectives  Demonstrate survivability of penetrator shell, accelerometers and power system.  Assess impact on penetrator subsystems and instruments.  Determine internal acceleration environment at different positions within penetrator.  Extend predictive modelling to new impact and penetrator materials.  Assess alternative packing methods.  Assess interconnect philosophy.

7. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK Trial Hardware Inners Stack

8. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK Impact Trial - Configuration  Rocket sled  Penetrator

9. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK Target  Dry sand  2m x2m x6m  Small front entrance aperture (polythene)

10. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK Firing

11. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK 1’st Firing - Results Penetrator found in top of target Glanced off a steel girder which radically changed its orientation. Penetration: ~3.9m Much ablation to nose and belly Rear flare quite distorted. Penetrator in one piece ✓ Firing parameters: Impact velocity: 310 m/s (c.f. 300m/s nominal) Nose-up ~10degs (c.f. 0 degs nominal) => worst case

12. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK Post Firing

13. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK First Firing – Opening up ssss

14. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK 1 st Firing – internal Results Micro seismometer bay Connecting to MSSL accelerometer and data processing bay

15. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK 1’srt Firing – QinetiQ accelerometer data Overview: 5 kgee smoothed, ~16 kgee peak high frequency components ~5khz Initial impact hi-res: Tail slap peak

16. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK 1’st Firing – MSSL accelerometer data Along axis:  Cutter: 3kgee  Main: 10kgee  Girder: 1kgee Along axis Vertical axis Horizontal axis FiringAlong axis VerticalHorizo ntal 1’st10 kgee15kgee4kgee 3’rd11kgee17kgee7kgee Peak gee forces in rear of penetrator 11 kgee 15 kgee 4 kgee GirderMain impactcutter

17. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK Hi-res MSSL accelerometer data Lots of high frequency structure

18. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK 2nd Firing “ Jaws-3?”..struck steel girder and moved it 6 inches

19. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK 2 nd & 3 rd Firings  All 3 firings remarkably consistent ~308-310m/s velocity, and ~8-10 degs nose up.  2/nd firing penetrator hit steel beam square on.  Penetrators survived all 3 firings. Payload still operational. Steel nose for 3rd firing

20. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK Survival Table ItemFiring 1Firing 2Firing 3 Penetrator ✓✓✓ Q-accel sys ✓✓✓ Rad sensor ✓n/a Batteries ✓n/a Drill assembly ✓ (mounting ?) n/a MagnetometerNot yet analysedn/a Micro seismometers n/a ✓ (protected) Mass spectrometern/aNot yet analysed (some loose screws) Not yet analysed MSSL accel sys ✓✓ (triggered prematurely) ✓ Triple worst case: exceed 300m/s, >8deg attack angle No critical failures – currently all minor to unprotected bays or preliminary mountings

21. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK Impact Trial Objectives Demonstrate survivability of penetrator body, accelerometers and power system. Demonstrate survivability of penetrator body, accelerometers and power system. Assess impact on penetrator subsystems and instruments. Assess impact on penetrator subsystems and instruments. Determine internal acceleration environment at different positions within penetrator. Determine internal acceleration environment at different positions within penetrator. Extend predictive modelling to new penetrator materials, and impact materials. Extend predictive modelling to new penetrator materials, and impact materials. Assess alternative packing methods. Assess alternative packing methods. Assess interconnect philosophy. Assess interconnect philosophy.

22. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK Next Steps & Strategy …  Next trial – aiming for Jan’09.  impact into harder material (ice,icy sand,concrete)  full-up system (all operating)  transmit from target  Parallel supporting studies Strategy: in parallel ‾Major developments for Lunar (MoonLITE) mission ‾Delta developments for icy planets

23. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK Penetrator website: http://www.mssl.ucl.ac.uk/planetary/missions/Micro_Penetrators.php email: rag@mssl.ucl.ac.ukrag@mssl.ucl.ac.uk Acheived major step in demonstrating confidence in technology Including impact survival into dunes & fluvial material - > next steps for harder materials and establishing larger engineering margins. No great history of failure - only 1 planetary delivery to date Significant TRL with previous space qualified technology A useful tool in the toolbox of planetary exploration Capable of addressing fundamental astrobiology signatures and habitability Provide ground truth & new information not possible from orbit Provide useful landing information for future missions. Penetrators Conclusions

24. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK - End -

25. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK What are Penetrators ? –Low mass projectiles ~5Kg+PDS for Enceladus –High impact speed ~ 200-500 m/s –Very tough ~10-50kgee –Penetrate surface ~ few metres –Perform science from below surface Penetrator Point of Separation Payload Instruments Detachable Propulsion Stage PDS (Penetrator Delivery System)

26. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK Penetrator Payload/Science A nominal 2kg payload …  Accelerometers – Probe surface/sub-surface material (hardness/composition)  Seismometers - Probe interior structure (existence/size of water reservoirs) and seismic activity of bodies  Chemical sensors – Probe surface refactory/volatile (organic/ astrobiologic) chemicals, perhaps arising from interior.  Thermal sensors - Determine subsurface temperatures and possibly probe deep interior processes.  Mineralogy/astrobiology camera – Probe surface mineralogy and possible astrobiological material.  + other instruments – to probe surface magnetic field, radiation, beeping transmitter, etc…  descent camera (surface morphology, landing site location, etc)

27. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK Enceladus - Science/Technology Requirements  Target –E.g. region of upwelled interior material. –2 penetrators would allow additional target, improved seismic results and natural redundancy but require 2xmass.  Lifetime –Only minutes/hours required for camera, accelerometer, chemistry, thermal & mineralogy/astrobiologic measurements. –An orbital period (~few days) for seismic measurements. (requires RHU)  Spacecraft support –~7-9 years cruise phase, health reporting  Delivery –Targetting precision. –Ejection, descent motors & orientation, pre-impact separation, communications, impact.  Operation –Power/thermal (battery/RHU), data handling, communications.

28. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UK Preliminary Mass Estimates Item Enceladus EnceladusTitanOrbitDeploymentTitanBalloonDeployment Penetrator (inc. 2 kg payload) ~4.5Kg ~4.5Kg Delivery system(*) ~32Kg~3.5-23Kg~2.5Kg Spacecraft support ~2.5Kg ~2.5Kg ~1.5-2.5Kg ~1.5-2.5Kg ~1.5Kg ~1.5Kg Total mass ~39Kg~12-30kg~8.5Kg (*) heavy penalty for Enceladus delivery: estimate ~8x(penetrator mass) with deployment from Titan with ∆V~3.7Km/sec

29. TSSM Meeting - Monrovia, Jun 02 2008 MSSL/UCL UKHeritage  Lunar-A and DS2 space qualified.  Military have been successfully firing instrumented projectiles for many years to comparable levels of gee forces into concrete and steel.  40,000gee qualified electronics exist (and re-used).  Currently developing similar penetrators for MoonLITE.  Payload heritage: –Accelerometers, thermometers, sample drill – fully space qualified. –Seismometers (ExoMars) & chemical sensors (Rosetta) heritage but require impact ruggedizing. –Mineralogy camera – new but simple. When asked to describe the condition of a probe that had impacted 2m of concrete at 300 m/s a UK expert described the device as ‘a bit scratched’!