8: Science Operations

1
IBEX Mission Operations Review (MOR)
8 Science Operations N. A. Schwadron
Orbital Sciences CorporationJuly 10-11, 2007
2
Orbit Orientation Good for Science

• Goal Sun 42º from line of apsides after launch
• Good orientation for Global ENA maps
• Hole from magnetospheric obscuration opposite the
  line of apsides
• 28º ( 42º-14º) from heliospheric tail
• Good orientation for Interstellar Oxygen and
  Helium measurements
• From day 10-60 (spring viewing), mag tail
  113º-63º from LOA
• From day 255 - 290 (fall viewing), mag tail
  132º-167º from LOA

Day 10-60
Day 255-290
3
Orbit in the Life of the ISOC

• Provide STF (if needed) to Orbital MOC (for
  special science maintenance operations)
• Monitor near real-time SOH during pass using VNC
• Retrieve raw back-orbit real-time data from the
  MOC SFTP site
• Remove telemetry framing info (Level 0.5)
• Sequence data, identify data gaps remove
  redundant data (Level 0.5)
• Generate Level 1 data
• Includes derived fields such as spin phase, look
  direction, background as a function of look
  direction
• Includes S/C ephemeris and attitude information
• Accumulate Level 1 data into Level 2 maps
• perform magnetospheric/heliospheric segregation,
  separate species, find velocity direction,
  identify and cull any backgrounds
• Perform model-dependent corrections for Level 3
  data and accumulate into maps

4
IBEX Data Flow
5
Interface Topology
6
ISOC Computing Hardware
To backup server
NETWORK
Logger
console
switch
LAN
Science
mux
wkstation
wksation
SOC
Maestro (SwRI)
Firewall
RAID 16x250 GB
Firewall
At BU ISOC
Firewall
UPS
At BU ISOC SwRI Mirror
Locked cabinet in key-coded room
Mirror
Secure LAN
Disk access
External networks
Semi-open LANs
Power supply
Multiplexed consoles
7
Files passed to and from MOC (1/3)
8
Files passed to and from MOC (2/3)
9
Files passed to and from MOC (3/3)
10
Orbit Events File Contents (1/2)

• Contains orbital events over the same period as
  the input ephemeris file (only events in orbit N
  used to generate commands)
• Orbit numbering
• Eclipse entry/exit times
• Umbra and penumbra times identified
• Flag for long (2 hour) eclipse
• Time of apogee and perigee
• Includes sun vector at the time of apogee, for
  re-pointing maneuver planning
• 10RE altitude crossing times, ascending and
  descending
• Star tracker outage start and stop times
• Each outage identified as either Earth or Moon
  outage
• Time of re-pointing maneuver
• IBEX-Lo Interstellar Oxygen Collection status
• See next slide
• Start/stop times for Moon in IBEX-Lo field of
  view
• Any time Moon is in field of view at any point in
  the S/C spin

11
Orbit Events (2/2)

• Note that oMode and oPlan provide the mechanism
  for determing the operational model of IBEX-Lo

12
Command Load Generation Automation

• Nominal operations command loads generated
  through automated rotes in MPS
• Command sequence for LAHO-HASO transitions
• Predefined sequence based on macros and simple
  timing rules
• Includes P/L mode change and S/C state change
• Timing and target vector of inertial re-pointing
  maneuvers
• MPS calculates these automatically, no user input
  required
• Automation includes properly timed commands to
  turn on catbed heaters
• Transmitter on-off times
• Commands generated automatically based on ground
  contact schedule confirmed by USN
• All command loads constraint checked in MPS and
  manually reviewed by MOC and ISOC
• Automated command list can be manually overridden
  at any time, as needed

13
Foundation for Data Products
14
Ground OperationsData Products Archiving
Latency
15
P/L OperationsOverview

• Science data collected above 10 RE HVSCI mode
• Sensors sweep energy channels
• Hi 6 Energy steps
• Lo 8 Energy steps

16
P/L OperationsNomenclature Data Collection

• Energy Step one ESA setting
• 2 spins (ESA step every 30 seconds _at_ 4rpm)
• Energy Sweep 6 (8) E steps for Hi (Lo)
• Hi 12 spins 3 min.
• Lo 16 spins 4 min.
• Energy Frame 4 E sweeps
• Hi 720 spins 12 min.
• Lo 960 spins 16 min.
• Syncing of Energy Frames every 48 min.

17
P/L OperationsIBEX-Lo Interstellar Oxygen

• IBEX-Lo also detects Interstellar Neutrals
• Begins after first 6 mo. of Nominal Ops
• Neutrals centered about the ecliptic
• O detection set as DOY driven flag in MPS
• Commanded through oMode and oPlan
• Restricted to 30 deg from ecliptic
• Fall (DOY 255-290)
• Use high (3.5º FWHM) and low (7º FWHM) resolution
  sectors of collimator for interstellar neutral
  observing
• Focus on Energy bin 2-3 (31 eV)
• Spring (DOY 10-60)
• Reject particles from low resolution sectors
  (with suppression voltage)
• For other 9 spins use single energy channel near
  430 eV for O sensing
• For every 10-th spin, look at Energy bin 1 to
  identify any possible He counts

18
Special P/L Maintenance Operations STF for Gain
Testing/Pressure Meas.

• Track MCP gain by ratios of Triple to Double
  Coincidence Rates
• Ground Software will provide ratios for trending
• Test procedure contains an automated series of
  internal stimulation settings, which completely
  tests analog electronics
• Run once per month
• Combine with Pressure Measurement (reduction of
  coll. e- rejection voltage) to increase count rate

19
Ground OperationsCommand Load Generation Input

• Absolute Time Sequence (ATS) command load
  generated by MPS in MOC
• 2 - 8 P/L commands per orbit
• P/L commanding macro driven
• Variable parameters set in Look Up Tables and
  called by macros
• Simplifies command load generation and validation
• Science Tasking File (STF) sent to MOC if Special
  Maintenance Operations desired
• STF input into MPS for incorporation into ATS
• Command load info received from MOC
• Record of successful ATS uplink
• Bit pattern of the uplinked ATS

20
Ground OperationsP/L Commands
Used Every Orbit
21
Ground Operations Trending

• Remainder of telemetry is housekeeping (H/K)
• Front-line on H/K checking in Maestro (at MOC)
  with red/yellow alarms
• Will repeat red/yellow limit checking at ISOC
• Formatted to allow quick lookups base and stored
  in telemetry database for easy cross-referencing
• Interpolation strategy TBD
• Heuristics to eliminate isolated noisy or
  unphysical values

22
Ground OperationsArchiving and Databases

• ISOC Database
• Trending
• SOH
• Searchable database
• Red/yellow alarm limit checks
• Telemetry to maps
• C programs for data harvesting
• DEs and histograms quality tagged
• Visualization toolbox (coordinate systems,
  overlays, etc)

23
Ground OperationsArchiving and Distribution

• ISOC (BU)
• Telemetry archive
• SOH
• Science archive with web distribution of data
  products to science team
• SwRI (Mirror)
• Mirrored science archive
• SPDF and NSSDC
• Level 1,2,3 to SPDF for active archive (CDF
  format)
• SPDF puts on active archiving public sites such
  as CDAWeb, SSCWeb, and OMNIWeb
• Virtual Heliospheric Observatory (VHO)
• New concept allowing users to interact with data
  stored at locations other than the SPDF CDAWeb
• Search tool that will not house any actual data
• To enable IBEX in VHO, ISOC plans to submit
  metadata to SPDF identifying where various data
  products are retrievable
• Validated Level 0, 1, 2, 3 data sent to NSSDC for
  permanent archive
• MOU with SPDF (John Cooper) and NSSDC (Ed
  Grayzeck) in process

24
Ground OperationsPlans for Web Interface
(SwRI-ISOC)

• Query for Level 1 and higher data products
• Filter data
• Visualizations showing viewing orientation/orbit
• S/C trajectory overlayed with magnetosphere
  projection
• Team page password protected
• Varying levels of data access
• Comply with ITAR restrictions
• Ensure data validity

25
Web Visualization Tool

• Java Application
• Plots IBEX data on a histogram as well as on the
  celestial sphere.
• Displays IBEXs trajectory for the selected bin
• Marks areas on plots with high background fluxes.

26
Selecting a bin in the Histogram or Global plots
highlights the corresponding bin in the other
plot.
27
Enabling an overlay whites out regions of data
where, for instance, IBEX is inside or looking at
the magnetosphere.
28
Payload Ops Testing

• IBEX-Lo Hi Calibration
• Long B/G runs in various sensor states
• Assembling cal results
• Cross-Cal at SwRI
• DE prioritization scheme
• Calibrated UV test
• Assembling cal results
• S/C Thermal Vacuum exercise voltage sweeping
• HVSCI
• Pressure Measurement

29
Science Software Testing

• Faux science data
• Faux data provide means to test software
• Includes S/C orbit, spinning, magnetosphere,
  heliosphere
• Convert data to faux telemetry
• Test schemes for packing, segregation, etc
• Procedures (incl. Regression Tests)
• Sort test (ISW-1) read in tlm, produce sorted
  list of DEs, ordered by time, energy, species,
  arrival direction -- Build 2
• B/G Test (ISW-2) read in tlm based on cal from
  Channel-D detector, decode, recover approximate
  beam intensities -- Build 2
• Magnetosphere segregation test (ISW-3) -- Build 2
• Orbit Products Test (ISW-4) -- Build 3
• Star-tracker Attitude History Test (ISW-5) --
  Build 3
• Star-sensor Attitude History Test (ISW-6) --
  Build 3
• Global View Tests (ISW-7) -- Build 5
• Command Sequence Tests (ISW-8) Command sequences
  tested with the Maestro workstation, Python
  scripts -- Build 2
• Housekeeping Tests (ISW-9) -- Build 2

30
Software Longevity Plan (1 of 2)

• Open-source code opted where possible
• Compiled code
• C- software for bulk of science code
• Also Java (for web interface), possibly Fortran
  (misc heritage science code, linkable with C)
• Scripted code
• Sh, Perl, Python, Javascript
• Command generation and verification initially
  using Maestro (COTS license through 1 year after
  launch)
• Eventually using Python/Perl/C code
• Code runs on Linux machines
• Gnu software tools
• SPICE
• COTS
• Maestro (Commanding, and Near Real Time
  Monitoring)
• VNC for monitoring near-real time passes

31
Software Longevity Plan (2 of 2)

• Documentation (Current documentation in
  components)
• IBEX Software Design Document (ISDD)
• Command Reference Manual
• IBEX PDMP
• ISDD will transition to IBEX Software Manual when
  SW reaches maturity
• Individual Sensor Documentation Currently Under
  Revision Process
• Archives
• Software and Documentation under Version Control
• Will be delivered with Final Products
• Open Data Policy

32
Ground OperationsScience Processing Repository

• Telemetry processed using series of C routines
• Sequence
• Remove redundant data
• Use ephemeris tables and pointing information
  (ancillary data) to derive position and attitude
• Perform binning, data harvesting
• Correlate DEs and histograms
• Routines to plot in GSE, GSM, RA DEC, HSE
  coordinate systems
• Overlay magnetospheric projections
• Data manipulated and harvested with series of
  option flags for filtering
• data never removed
• Overlays include star maps, planets, the moon,
  magnetosphere, possibly bright comets
• Data storage not an issue
• data volume small estimate of total data volume
  including data products and stored data
  reports, less than 50 GB

33
Interface Testing

• MOC/ISOC Telemetry Receipt and Analysis Test
  (IGS-4)
• ISOC runs Maestro to monitor Tlm, receive P/L PB
  and H/K through secure ftp, verify P/B consistent
  with recroded data
• Thermal Vac Test
• Calibration data (UV source), test sensor modes
• Cross-Cal at SwRI
• Test priortization scheme, O-sensing mode,
  Calibrated UV test, long B/G runs in various
  sensor states
• VNC Test (MOC-ISOC, ISOC-T1)
• ISOC/MOC Command Processing Test (IGS-6)
• MOC sens ISOC ATS files and the ISOC will verify
  P/L command sequences, ISOC sends multiple STF
  files for special ops, MOC verifies format and
  procedures
• MOC/TDRSS Commanding Test (is this needed with no
  TDRSS?) (IGS-7)
• ISOC runs Maestro to monitor TDRSS Tlm
• MOC/USN Commanding Test (IGS-8)
• ISOC runs Maestro to monitor USN Tlm, retrievs
  P/L PB w/sftp, check consistency
• Backup MOC/USN Commanding Test (IGS-9)
• ISOC runs Maestro to monitor USN Tlm, retrievs
  P/L PB w/sftp, check consistency
• MOC Authorization Access Test (IGS-10)
• Demonstrate authorization access of workstation
  and commanding functions, sftp pf mission
  planning products between MOC and ISOC
• End-to-End Tests (IGS-11)
• ISOC checks abilit to receive/process orbit data,
  attitude data, command load checks (ATS files),
  STF loads for spacial ops, P/L PB and H/K, and
  ISOC receives a copy of uploaded commands

34
Science Team Deliverables

• Need Transfer function from 100 AU - 1 AU
• Bzowski
• Heerikuisen
• Interstellar Parameters
• Frisch
• Analytical Transfer Functions
• Roelof and Gruntman
• Specific Modeling Products
• Magnetosphere Model

35
Summary

• IBEX Development Going Strong
• There are Issues that are being worked
• CEU Software
• Spin Pulse from ACS system
• At this meeting we should work to identify items
  that the science team is willing to provide to
  aid in the analysis and unterpretation of IBEX
  data

36
Response and Calibration
37
Response BreakDown
38
Geometrix Factor
39
Point Spread Function
40
Conversion Energy and Transmission Function
41
Yield Matrix
42
Fill in Blanks
43
BG Monitor
44
(No Transcript)