1. Challenges and progress with the development of a Lunar Laser Ranger for South Africa Ludwig Combrinck Roelf Botha ludwig@hartrao.ac.za Space Geodesy Programme Hartebeesthoek Radio Astronomy Observatory In collaboration with Observatoire de la Côte d’Azur 18th International Workshop on Laser Ranging - Pursuing Ultimate Accuracy & Creating New Synergies - 11-15 November 2013 Fujiyoshida, Japan

2. Japan, November 2013 2 Space Geodesy at HartRAO SLR, VLBI, GNSS, DORIS, Geophysical instruments….now LLR in development VLBI2010 2014-2016 MOBLAS-6, part of NASA SLR network, 100 mJ, 200 pico-second pulse, precision about 1.5 cm Cannot do Lunar Laser Ranging, system too weak and not designed for LLR 2 VLBI antennas, VLBI2010 antenna construction starting 2014

3. Japan, November 2013 3 No LLR currently in Southern Hemisphere; The SA LLR will be part of the GGOS network and part of the NASA SLR network A Southern Hemisphere LLR will strengthen the geometry of the LLR network and should improve the determination of the orientation of the Moon A dual system S/LLR will provide added coverage of SLR data in an area very sparsely covered Currently 4 active LLR systems, 2 in development Apache point Active LLR system In development LLR system The concept of an LLR for the southern Hemisphere was discussed at the13 th International ILRS Workshop (October 2002) in Washington at an LLR breakaway meeting, where community support was given in principle. I had previously discussed the idea with Etienne Samain (OCA, France). Originally I had tried t o obtain use of a 30” telescope at Sutherland, South Africa, proposal at SAAO meeting 26 April 2003.

4. Japan, November 2013 4 Ex-Observatoire de la Cote d’Azur 1-m SLR telescope 1-m SLR FTLRS LLR Removed 30 Aug 2005

5. Japan, November 2013 5 Overall design concept is software-centric Central Computer Control LLR Software Telescope and housing subsystem Detection and timing Hardware control and monitoring Laser subsystem Safety (interrupts, aircraft, smoke/fire) External inputs, remote access, data links On-site data evaluation and processing

6. Japan, November 2013 6 Software design; shared memory concept Dynamic Data Exchange LLRSteer LLRServo- Control MS Excel Hardware Control Micro- processor software

7. Japan, November 2013 7 Telescope housing 2.5 minutes to open and move away Can be dismantled and moved to final location Large enough to allow maintenance access via crane All metal construction Steel reinforced massive concrete floor Housing runs on tracks via electrical motors 1 ton crane to remove gearbox and instruments

8. Japan, November 2013 8 ‘Temporary foundation’ Telescope housed in run- off enclosure Crane to assist in disassembly and refurbishment Totally nuts and bolts construction to facilitate future removal to appropriate site Stable and massive foundation for tests

9. Japan, November 2013 9 50 cubic metres of concrete…

10. Japan, November 2013 10 Run-off enclosure on steel tracks

11. Japan, November 2013 11

12. Japan, November 2013 12 Tie to ITRF via GNSS Mount installed 2 June 2011 Much restoration work ahead!

13. Gearboxes were removed, disassembled, refurbished, modern oil Japan, November 2013 13

14. Tube has been restored Japan, November 2013 14

15. All panels and Az-El mount repainted with heat reflecting paint Japan, November 2013 15

16. Japan, November 2013 16

17. Japan, November 2013 17 Laser system by Cybioms Corporation 100 mJ, 20 Hz, <80 ps; 1KHz, 0.5 mJa

18. Testbed 12.5 cm f12.5 refractor (i.e. what my lunch times are spent on) Micro-processor controlled functions Dual servo control system, all software in-house (or rather late-at-night)

19. Main and secondary to be re-aluminized and coated Japan, November 2013 19

20. Japan, November 2013 20 Control centre based on 12 m shipping container; clean air filters Located next to MOBLAS-6 Curved roof to provide shade

21. Japan, November 2013 21 Control centre designed for desert conditions Insulation panels fitted externally and internally Rubberised floor Dedicated air conditioner in laser room Positive air pressure to keep dust out

22. UPS 20 KVA Japan, November 2013 22

23. Control room Japan, November 2013 23

24. Japan, November 2013 24 Project completion 2015? 2016? Where will the system be located?

25. Japan, November 2013 25 Thank you! Acknowledgements Thanks to the LOC for a fantastic workshop! Projects such as these depend to a large extent on international collaboration. We specifically thank OCA (France), NASA (USA) and Cybioms Corporation (USA). Funding received from the National Research Foundation (NRF), South Africa, towards this project is appreciated. This work is based on research supported by NRF grant IFR2011041500034.