LRO Operations Concept
Richard Saylor Jr.
HTSI/Code 444
August 16-17, 2005
NASA’s Goddard Space Flight Center
14 - 1
Operations Concept Development
Level 1 Requirements
Level 2 Requirements
(MRD)
(431-RQMT-000006)
LRO Level 3
Requirements
LRO Concept of Operations
(431-OPS-000046)
LRO Flight
Operations Plan
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•
LRO Mission
Operations Support
Plan
LRO Flight
Operations
Contingency Plan
LRO Flight
Procedures
Documents
Level 1, 2, and 3 requirements are used in the development the mission operations concept
The operations concept describes the operational plan which will be used around the
framework of the requirements
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•
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LRO Project
Database
Management Plan
Document will be updated as the mission designs evolves
Initial version of the Lunar Reconnaissance Orbiter Concept of Operations is available
From the operations concept, lower level operational support documents will be developed
NASA’s Goddard Space Flight Center
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LRO Mission Phases
No
Phase
Sub-Phases
Description
1
Pre-Launch/ Launch
readiness
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Space Segment Readiness
Ground Segment
Readiness
Includes instrument I&T, spacecraft/orbiter I&T, space/ground segment testing
as well as operations preparation and ground readiness testing leading up to
launch.
2
Launch & Lunar
Transfer
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Launch and Ascent
Separation and De-spin
Deployment and Sun Acq.
Lunar Cruise
Lunar Orbit Insertion
Includes all activities & operations from launch countdown sequence to Lunar
Orbit Insertion (LOI). LOI includes all maneuvers necessary to obtain the
temporary parking orbit for Orbiter activation and commissioning. During the
cruise phase, initial spacecraft checkout will be performed to support activities
for mid course correction (MCC) and LOI.
3
Orbiter Commissioning
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Spacecraft Commissioning
Integrated Instrument
Commissioning
Configure and checkout the spacecraft subsystems and ground systems prior
to instrument turn-on. Instrument integrated activation will be developed to
complete instruments turn-on and commissioning. Instrument commissioning
includes any calibration activities needed in the temporary orbit.
4
Routine Operations

Measurements (Routine
Ops)
Station-keeping
Momentum Management
Instrument Calibrations
Lunar Eclipse
Yaw Maneuver
Safe Mode
One year of nominal science collection in the 50 (+/- 15) km orbit.
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5
Extended Mission
Operations
After 1-year of science observations, orbiter may be boosted into a higher orbit
to reduce maintenance requirements. Potential goals for extended mission
are:
– Perform relay comm. operations for 2nd RLEP mission.
– Collect additional measurement data at the nominal mission orbit
– Take additional measurement operations in a higher orbit.
6
End-of-Mission Disposal
NASA’s Goddard Space Flight Center
Includes planning and execution of end-of-life operations.
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Mission Phase Summaries
Launch and Cruise Phase
Phase Begins:
Approximately L-18-hrs (start of launch vehicle countdown procedure
Phase Ends:
Completion of Lunar Orbit Insertion (LOI) maneuvers. Orbiter is captured in commissioning orbit.
Sub-Phases:
Launch and Ascent, Separation, Deployment and Sun Acquisition, Lunar Cruise, Lunar Orbit Insertion
Key Orbiter
Activities:
•
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C&DH monitors and detects separation from launch vehicle, triggers separation sequence which controls
activities through Deployment and Sun Acquisition sub-phase.
Deploy solar array boom and panel.
Acquire Sun and perform ground acquisition for telemetry and commands.
Start spacecraft bus commissioning activities.
Perform mid-course correction (MCC) maneuver within 24 hours of launch.
Turn on CRaTER and LEND for early calibration activities during the flight to lunar orbit.
Deploy high gain antenna.
Key Ground
Activities:
•
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•
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Use all networks including DSN to support early mission objectives.
Provide S-Band tracking data to flight dynamics for MCC planning.
Dump and analyze orbiter housekeeping data.
Verify ground system configuration (use different S-Band telemetry rates).
Process real-time housekeeping data for engineering team.
Execute pre-define sequence of events.
Support Plan:
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•
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Mission Operations Team (MOT) staffs the MOC 24x7 until LRO captures into commissioning orbit.
Spacecraft engineering team staffs the MOC
Instrument engineering team staffs the MOC for CRaTER and LEND. Other instrument team staff depends on
potential instrument contingencies defined later.
Goal is to perform prime commissioning activities during prime shift. Backup shift will mostly monitor orbiter
operations and prepare for next day activities.
•
NASA’s Goddard Space Flight Center
14 - 4
Key Early Mission Activities
NASA’s Goddard Space Flight Center
14 - 5
Mission Phase Summaries
Orbiter Commissioning Phase
Phase Begins:
After orbiter insertion into the commissioning orbit of 30x216 km.
Phase Ends:
Completion of instrument commissioning and insertion into the mission orbit of 50 km.
Sub-Phases:
Spacecraft Commissioning, Integrated Instrument Commissioning
Key Orbiter
Activities:
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C&DH commissioning
Test and calibrate solar array and high gain antenna pointing
Verify Ka downlink telemetry
Perform sensor and alignment calibration activities
Configure the spacecraft fault detection and handling components
Power instruments according to the integrated instrument commissioning plan
Perform functional checks with each of the instruments
Execute instrument calibration activities according to the instrument calibration/validation plan
Perform series of thruster maneuvers to capture into the mission orbit
Key Ground
Activities:
•
Use primary ground network stations for support (White Sands, Australia, Belgium, Kiruna, and Hawaii). DSN will
be used for backup and contingency activities.
Flight dynamics will analyze commissioning orbit and verify whether frozen orbit exist at the 30x216 orbit. Data
could be used later for planning of extended mission.
Verify file data delivery concept and distribution links to each of the instrument science operations center.
Backup MOC will be checked out.
•
•
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Support Plan:
•
•
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MOC will be staffed approximately 16-hrs/day during commissioning phase. Non-critical automation tools will be
verified prior to reduced staff hours.
MOC will be staffed will spacecraft and instrument engineering teams to support planning and real-time
monitoring of the orbiter.
Most activities will be performed on the prime shift, backup shift will monitor and prepare for next day activities.
NASA’s Goddard Space Flight Center
14 - 6
Mission Phase Summaries
Routine Operations Phase
Phase Begins:
Starts after insertion into the mission orbit of 50 km and completion of instrument commissioning.
Phase Ends:
Ends after 12 months from the start of routine operations phase.
Sub-Phases:
Measurement Operations, Station-Keeping, Momentum Management, Instrument Calibrations, Lunar Eclipse, Yaw
Maneuver, Safe Mode
Key Orbiter
Activities:
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•
•
•
•
•
•
Key Ground
Activities:
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•
•
•
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Support Plan:
•
•
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•
Spacecraft will nominally be nadir pointing.
Momentum management will be performed every 2-weeks while in contact with the ground.
Station-keeping maneuvers are done every month, requires two burns during 1 orbit.
Once a month, around the station-keeping maneuvers, instrument calibrations will be coordinated with instrument
science teams. Currently allocated approximately 3 orbits for calibrations activities.
Roughly twice a year, LRO may be affected by lunar eclipse, orbiter might be commanded to low power mode.
Twice a year, near the beta angle condition, the spacecraft will perform a 180° yaw maneuver.
Once a month, operate mini-RF technology demonstration. Operating times will be perform around monthly
station-keeping maneuvers.
Use primary ground network stations for support (White Sands, Australia, Belgium)
Back network S-Band support will be provided by Kiruna, Hawaii, and DSN.
Ka-Band measurement data will be dumped during the White Sands Ground Station view period each day.
Roughly 4 contacts each day.
Data will be distributed to each instrument SOC for level 0 and higher data processing.
Ground will use reliable transfer protocol to verify data files from the spacecraft recorded is received on the
ground.
MOC will be staffed 5 days a week (Monday-Friday), 8-hr shift. Automation will monitor ground and orbiter health
and safety.
Flight operations team will also perform parallel/proficiency activities using the backup MOC.
Flight operations team will call upon the development spacecraft engineers for anomaly support.
Instrument SOCs will be responsible for all instrument maintenance.
NASA’s Goddard Space Flight Center
14 - 7
LRO’s View of the Universe
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NASA’s Goddard Space Flight Center
Twice a year, LRO will be in full Sun for roughly
one month for each event. The full Sun
condition occurs when the orbit Beta angle
reaches ~76°.
During the eclipse season (the shaded portion
of the Sun circle), LRO is expected to have a
maximum lunar occultation of 48 minutes. The
maximum duration lunar occultation will occur
when the orbit beta angle reaches 0°.
Twice a year, LRO will be required to perform a
180° yaw maneuver. The yaw maneuvers will
be performed as the orbit approaches the beta
0° condition.
Twice a month, LRO’s orbit will be in full view of
the Earth for a period of ~2 days. During the 2
days, ground stations on the Earth will have
continuous view of LRO. However, due to the
HGA range of motion limitation, the HGA ground
contacts will still be limited to approximately 56
minutes. The omni antennas can provide
continuous coverage.
Twice a month, LRO will perform momentum
management. The maneuver will occur when
the ground has complete coverage of the orbit.
Once a month, LRO will perform station-keeping
(SK) maneuvers to maintain the mission orbit.
The station keeping maneuver will be performed
when the ground stations has complete
coverage of the orbit.
Twice a year (on average), the Earth will pass
between the Moon and the Sun (Lunar Eclipse).
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Integrated Instrument Operations
LRO Baseline Instruments Operating Modes
~103 W
~105 W
Instrument Avg.
Orbital Power
~105 W
~96 W
~90 W
~90 W
~88 W
~88 W
~6.35 Mbps
Instrument Avg.
Data Rate
~0.14 Mbps
LAMP Operating
Mode
~0.14 Mbps
Constant Data Rate ~20.2 kbps
CRaTER Operating
Mode
HV Enable
HV Disable
Constant data rate ~100 kbps (During Flares), Non flares ~0.2 kbps
Diviner Operating
Mode
Constant data rate ~10.6 kbps
LEND Operating
Mode
Constant data rate ~0.035 kbps
LOLA Operating
Mode
Constant data rate ~10 kbps
LROC Operating
Mode
Constant Data Rate ~20.2 kbps
WAC
WAC (1 Mbit Image/Sec)
LROC
Power
Cycle
NAC 2 (Each Image ~256 MB)
NAC 1 (Each Image ~256 MB)
Non Sun Lit, Total time
~56.5 minutes
NASA’s Goddard Space Flight Center
Moon’s
Pole
Sun Lit ~56.5 minutes
Moon’s
Pole
Non Sun Lit, Total time
~56.5 minutes
14 - 9
Predicted Daily Data Volume
LRO Data Calculation Summary
Data Source
LOLA
LEND
LAMP Sci
LAMP HK
CRaTER
Diviner
LROC WAC
LROC NAC
Spacecraft HK
Raw Rate
(kbps)
10
0.6
20.2
0.8
100
10.6
598
N/A
32
Data
Op Time Raw Data Orbit Data Daily Data Daily Data Daily Data
Rate
Min Per File Size
per Orbit per Orbit w/CCSDS w/CCSDS w/CFDP OH w/R-S OH
w/OH
File
(Mbits)
(min)
(Mbits)
OH (Mbits) OH (Mbits)
(Mbits)
(Mbits)
(kbps)
10.50
113.0
66.21
69.52
885.94
912.52
1,049.39
10.0
6.15
0.63
113.0
3.97
4.17
53.16
54.75
62.96
113.0
4.17
21.21
56.5
66.87
70.22
894.80
921.64
1,059.89
10.0
12.43
0.84
113.0
5.30
5.56
70.88
73.00
83.95
113.0
5.56
105.00
113.0
662.11
695.21
8,859.38
9,125.16
10,493.93
1.3
8.00
11.13
113.0
70.18
73.69
939.09
967.27
1,112.36
10.0
6.52
598
56.5
1,979.71
1,979.71
25,228.13
25,984.97
29,882.71
5.0
175.20
N/A
56.5 38,550.59
38,550.59 491,264.13 506,002.06 581,902.37
N/A
1,204.71
32
113
211.88
222.47
2,835.00
2,920.05
3,358.06
10.0
18.75
SSR Daily Storage w/CCSDS OH:
SSR Daily Storage w/CCSDS & CFDP OH:
SSR Orbit Storage w/CCSDS OH:
SSR Orbit Storage w/CCSDS & CFDP OH:
Total Data to be dumped daily w/all OH & Coding:
NASA’s Goddard Space Flight Center
518.58
534.14
40.69
41.92
1,228.53
File Size
(kBytes)
787.50
533.93
1,590.75
711.90
1,023.75
834.75
22,425.00
154,202.35
2,400.00
Files per Files per
Orbit
Day
11.3
1.0
11.3
1.0
86.9
11.3
22.6
32.0
11.3
188.7
144.0
12.7
144.0
12.7
1,107.7
144.0
288.0
407.8
144.0
2,405.0
Gbits
Gbits
Gbits
Gbits
Gsymbols
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Predicted Data Downlink Concept
LRO 1-Ka Ground Station (White Sand) Dump Scenario
Data Volume w/CCSDS OH (Min):
Data Volume w/CCSDS OH (Max):
Data Volume w/CCSDS & CFDP OH (Min):
Data Volume w/CCSDS & CFDP OH (Max):
Pass Length:
Time Since Last Pass:
Orbits Since Last Pass:
Data Recorded (Min):
Data Recorded (Max):
Data to be Dumped (Min):
Data to be Dumped (Max):
Symbols (Min):
Symbols (Max):
D/L Capacity:
Remaining Data (Min):
Remaining Data (Max):
Minutes Remaining (Min):
Minutes Remaining (Max):
NASA’s Goddard Space Flight Center
Daily
308.69 Gbits
518.58 Gbits
317.95 Gbits
534.14 Gbits
Contact #1
45 minutes
1044 minutes
9.24 orbits
223.80 Gbits
375.97 Gbits
230.52 Gbits
387.25 Gbits
544.02 Gsym
913.92 Gsym
606.45 Gsym
0.00 Gbits
130.28 Gbits
4.63 minutes
-22.82 minutes
Orbit
24.22 Gbits
40.69 Gbits
24.95 Gbits
41.92 Gbits
Min. View Period at White Sands
Contact #2
Contact #3
45 minutes
45 minutes
113 minutes
113 minutes
1 orbits
1 orbits
24.22 Gbits
24.22 Gbits
40.69 Gbits
40.69 Gbits
24.95 Gbits
24.95 Gbits
172.20 Gbits
41.92 Gbits
58.88 Gsym
58.88 Gsym
406.39 Gsym
98.92 Gsym
606.45 Gsym
0.00 Gbits
0.00 Gbits
40.63 minutes
14.84 minutes
606.45 Gsym
0.00 Gbits
0.00 Gbits
40.63 minutes
37.66 minutes
Contact #4
45 minutes
113 minutes
1 orbits
24.22 Gbits
40.69 Gbits
24.95 Gbits
41.92 Gbits
58.88 Gsym
98.92 Gsym
606.45 Gsym
0.00 Gbits
0.00 Gbits
40.63 minutes
37.66 minutes
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Daily Operations Timeline
NASA’s Goddard Space Flight Center
14 - 12
One Week Operations Profile
NASA’s Goddard Space Flight Center
14 - 13
Ground System Architecture
NASA’s Goddard Space Flight Center
14 - 14
Data Flow Discussions
• All commands will originate from the mission operations
center
– Instrument SOCs will delivery request and timelines as required
– MOC will process and generate command loads or incorporate
request into the daily pass activities
• White Sands receives S/Ka downlinks
– Ka-Band measurement data is transferred to MOC for processing.
MOC distributes the data to each of the instrument SOCs.
– MOC also will distribute mission planning products to ground system
elements as required
• Real-time housekeeping data is received at the MOC for
monitoring orbiter health and safety
NASA’s Goddard Space Flight Center
14 - 15
Mission Phase Summaries
Extended Mission Operations Phase
Phase Begins:
Starts after nominal mission phase ends, approximately 14 months after launch.
Phase Ends:
Ends when disposal phase begins.
Sub-Phases:
None
Key Orbiter
Activities:
•
Key Ground
Activities:
•
•
Use primary ground network stations for support (White Sands, Australia, Belgium)
Back network S-Band support will be provided by Kiruna, Hawaii, and DSN.
Support Plan:
•
MOC will be staffed 5 days a week (Monday-Friday), 8-hr shift. Automation will monitor ground and orbiter health
and safety.
Flight operations team will call upon the development spacecraft engineers for anomaly support.
Instrument SOCs will be responsible for all instrument maintenance.
Activities will be dependent on objectives during phase:
– Communication relay for next lunar mission
– Extended measurement operations in mission orbit or higher lower maintenance orbit.
•
•
NASA’s Goddard Space Flight Center
14 - 16
Mission Phase Summaries
End-of-Mission Disposal Phase
Phase Begins:
Starts when extended mission operations is declared over.
Phase Ends:
Orbiter impact on the Moon and mission closeout activities are completed.
Sub-Phases:
None
Key Orbiter
Activities:
•
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Remaining fuel will determine when mission will impact. Plan is to continue until all fuel is used.
Depending on discovery during the mission, the impact zone may be selected otherwise, there is no requirement
on impact location.
Key Ground
Activities:
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•
Plan to support end-of-mission activities. Develop end-of-mission plans and define closeout activities.
Tracking, if possible, the orbiter trajectory as it impacts the Moon.
Support Plan:
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MOC will be staffed according to the detailed de-orbit plans.
Closely supported by flight dynamics and spacecraft engineers.
NASA’s Goddard Space Flight Center
14 - 17
Mission Operations Team Staffing
• Mission Operations Center will be located at GSFC
• The mission operations team will support ground system and orbiter
development prior to launch
– Operations team will augment ground system test team, useful in providing
training to the operations team
– Operations team will provide test engineers for instruments, spacecraft box
level, spacecraft bus, and orbiter level integration and test.
• Help develop test procedures, command & telemetry databases, develop Users
Guide and other related operations documentation
• Provide ground system expertise
– I&T will use the same Command and Telemetry system
– Other systems will be shared such as the anomaly system
• Staffing plan calls for gradual decrease in operations staffing level as the
mission progress from commissioning to routine.
– Rate of decrease will be dependent on mission activities and verification of
automation
NASA’s Goddard Space Flight Center
14 - 18
Summary
• Initial operations concept has been developed for the
mission
– Lunar Reconnaissance Orbiter Mission Concept of Operations
Document is available for review
• Operations defined in document have been and continue to
be included as part of the mission design
– The operations document will continue to mature in preparation for
mission PDR, but existing requirements are compatible with the
concept.
NASA’s Goddard Space Flight Center
14 - 19