1. Computing for Space Science – Current practice and future challenges Peter Allan Head, Space Data Division

2. Overview Brief overview of work of SSTD Software, data, archives Systems in space Challenges for the future

3. Work of SSTD Astronomy and Earth Observation Design studies Design, build and test instruments Launch instruments (e.g GERB on Wednesday) Science Operations Communicate with spacecraft Develop data processing systems Process, archive and disseminate data Long term data curation Telescope pointing

4. GERB Internal black- body Front End Electronics Scan Mirror Telescope Calibration Monitor Quartz Filter Earth View Fold mirror and detector 18g

5. Launches

6. RAL Ground Station RAL antennae 12m plus 2.4m Chilbolton 25m Jodrell Bank 76m NASA DSN –several hundred 10m-class antennae ?

7. Ground Stations Equipment controlled by standard PC Standard protocols are the key –Developed by CCSDS Like IP, but tuned for use in space –Must handle long round trip times (many mins to hours) –Must handle disjoint connections –Power is always at a premium

8. Science Operations Operations on Cluster Double Star Mars Express

9. General Computing Windows and Linux on desktop –A few Sun and HP workstations Linux, Solaris and Tru64 on science servers Windows servers for office system and technical tools (e.g. CAD)

10. Data Centres and Archives British Atmospheric Data Centre NERC Earth Observation Data Centre Cluster/Doublestar UK Solar System Data Centre –Solar data –Data on Ionosphere –Space plasma data

11. Software Engineering ISO 9001 Apply the “appropriate level” of rigour Use appropriate methods –Iterative development –Science code  industrial strength app –Develop formal requirements Workshops on improving processes –Use of standard tools? –Departmental CVS repository?

12. Operating Systems for Space Operating systems for space –H/W is previous generation –No disk drives –Tapes replaced with solid state memory –Still use assembler for some applications –Starting to use unix-like systems –Web server in space

13. Data Analysis and Visualisation Languages –Fortran, C, C++, Java, Perl, Python IDL –ENVI

14. Data Processing and Analysis Starlink GGSPS AstroGrid NERC data grid

15. Starlink Software for processing astronomical data for nearly all wavelengths Integrated data processing tools Library for writing new tools Uniform data format Fortran  (+C)  Java Lasted for 26 years

16. GGSPS GERB Ground Segment Processing System Multi-national data processing system –Germany  RAL  Belgium  RAL  Users Written in C++ (mostly not OO)

17. 256 detector pixels 282 steps Satellite rotation period = 0.6 s 282 steps for full Earth disc = 169.2 s Between each Earth scan, internal BB measurement taken for calibration At correct viewing geometry, calibration monitor records scattered solar light as a relative measure over time Average three scans in each channel to improve S/N Total repeat time = 169.2*6 ~ 15 min. 2 channels: Total Total+quartz filter (SW)

19. Future Challenges Autonomy –Rovers on Mars –On board analysis of satellite imagery Interplanetary Internet Integrating Grid computing into daily work

20. Interplanetary Internet Spread communications infrastructure throughout solar system E-mail rover1@syria-plenum.mars.sol Need the right protocols –Long round trip times!

21. Grid Computing AstroGrid NERC Data Grid Both about improving access to data –Search, merge, analyse Hooked into international data sources –IVOA

22. Grid Computing Examples from AstroGrid –Improving access to data –“What if” questions answered in minutes, not months –Enabling rapid response to sudden bursts

23. Optical Data ArchiveX-ray Data Archive Processing Pipeline Astronomy from the Desktop

24. multi- views of a Supernova Remnant Shocks seen in the X- ray Heavy elements seen in the optical Dust seen in the IR Relativistic electrons seen in the radio

25. Needles in a haystack Hambly et al 2001 - faint moving object is a cool white dwarf - may be solution to the dark matter problem - but hard to find : one in a million - even harder across multiple archives

26. yesterday browser front end CGI request html web page DB engine SQL data

27. today application web service SOAP/XML request SOAP/XML data DB engine SQL native data anything standard formats

28. tomorrow application web service job results anything web service web service web service web service web service Registry Workflow GLUE Certification VO Space standard semantics publish WSDL grid connected

29. Image from ESO Image + IRIS data Gamma Ray Bursts D. Ducros, ESA Reprocessing of ionospheric STP data change coords from earth to celestial Collate data from multiple telescopes over months - meta data issues Localise GRB alert in minutes – as fade rapidly. SWIFT satellite observes gamma ray burst Compare against SN light curves – bump shows eveidence for a SN in the GRB (Price et al, 2002) Interaction with observatory pipe- lines Cross reference multi- λ data – ID pre-cursor and or environment Large computational photometric redshift calcs on multi-λ > gives distance

30. Questions ?

31. yesterday browser front end CGI request html web page DB engine SQL data

32. today application web service SOAP/XML request SOAP/XML data DB engine SQL native data anything standard formats

33. tomorrow application web service job results anything web service web service web service web service web service Registry Workflow GLUE Certification VO Space standard semantics publish WSDL grid connected