Mars Odyssey PSG

Mission Status

Gaylon W. McSmithRobert A. Mase

June 9, 2003

Mars Odyssey Mission Status

Spacecraft operations are nominal

All Science payload suites are collecting data in a nominal fashion

April 7, 2003 marked the 2-year anniversary of Odyssey launchOn this date, we completed our 5000th mapping orbit

Mission Statistics (May 2003):

• Day 443 of the 917-day science mission (48% complete)

• Day 338 since GRS Boom Deploy (49% of one Mars-year)

• Total # Mapping Orbits: 5380 (6196 since MOI)

• 761 days past Launch (61% of mission complete)• Launch: April 7, 2001 End of Primary Mission: August 24, 2004

Science Data Return:

• Total Science Data Returned to Date: ~155 Gbytes

• Planned Data Volume for 917-day Science Mission: 126.5 Gbytes

• DSN allocations better than planned, operations enhancements

Total Fuel in the Tanks (Feb 2002): 46.2 kg ± 3 kg

Unusable 2.4 kg

Total Fuel Available for Mapping (Feb 19, 2002):43.8 kg

Expected Actual Usage

Allocation* Usage to Date (1 May 2003)

Contingency 8.2 kg 2.6 kg 0.0 kg

Safe Mode 5.0 kg 1.6 kg 0.2 kg

Momentum Mgmt 11.5 kg 3.7 kg 2.0 kg

Orbit Maintenance 3.7 kg 1.2 kg 0.0 kg

Extended Science 1.9 kg - 0.0 kg

PQ Orbit Raise 3.4 kg - 0.0 kg

Unallocated 10.1 kg - 0.0 kg

Total 43.8 kg 9.1 kg 2.2 kg

Total Usable Propellant Remaining: 41.6 kg ± 3 kg

* Allocations for 1374-day mission

Mars OdysseyPropellant Budget

Mars Odyssey Recent Spacecraft Activity

Recent Spacecraft Activity

Jan-Apr: Executed 14 NSP Demo Passes (18 Scheduled)

Jan 7: Activated the MARIE auto-download/erase block

Jan 15: Increased THEMIS APID30 packet buffer allocation

Jan 24: Uplinked Safe-Mode emergency desat parameters

Jan 27: Multi-Spacecraft DOR demo pass (w/ MGS)

Feb 4: Solar Array gimbal cycle and reposition

Feb 4: 110 kbps data rate at 70m stations

Feb 13: Updated DPT for small-packet issue

Feb 22: Multi-Spacecraft DOR demo pass (w/ MGS)

Apr 7: Completed 5000th Mapping Orbit

Apr 10: Demonstration of 124 kbps data rate

Apr 28: Solar Array gimbal cycle

Mars Odyssey Plans for Next Quarter

Plans for the next 3 months

• Continue UHF relay capability development and testing

• UHF testing with MER test-set at LMA (May 5-9)

• Complete UHF Stanford test plans

• Execute tests in June - Sep 2003

• Continue OTM planning for Sun-synchronous maneuver (Oct 2003)

• Plan for Demo tracks to prepare for Asset Contention Period (ACP)

• DEMOs with Parkes and New Norcia

• Arraying in an MSPA configuration

• 2-MSPA with uplink swaps

• Continue DOR campaign to support MER (thru Nov 2003)

• Study phasing ODY orbit to support MER SOL-1 overflight

Mars Odyssey Schedule

Activity NameJan Feb Mar Apr May Jun Jul Aug Sept Oct Nov Dec

2003

Jan Feb Mar Apr May Jun Jul Aug Sept Oct Nov Dec

Odyssey PSG

Quarterly Management Review

NSP Project Interface Demo

Update Project Risk List

UHF Block Development/TestingMER STE in Denver for Testing with ODY STL

ODY UHF Test (with Stanford)

UHF ORT Testing (with MER & Beagle2)

Propulsive Maneuver (OTM)

DSN Capability Demos(Array, MSPA, Alternate Assets)

DDOR Campaign (MER support)

Beagle 2 UHF Relay Support

MER-A UHF Relay Support

MER-B UHF Relay Support

• Transition to NSP is complete

• All stations are now transitioned to NSP or down for NSP upgrade

• During Feb - April, up to 4 of 10 stations were down at once for upgrade

• ODY had less tracking, more MSPA than usual

• ODY impacted by stations not returning to service on schedule

• And by changing DEMO tracks

• Future Capability Upgrades that will impact Odyssey

• All will require ODY demonstration tracks in the fall to prepare for the Asset Contention Period (ACP)

• 2-MSPA with multiple uplink swaps

• Array capability with MSPA

• Alternate Assets - in case of spacecraft emergency during ACP

• Parkes and New Norcia, both in Australia

Mars Odyssey Network Simplification Project (NSP)

• Program desire to characterize ODY UHF system

• Discovered 6dB (forward) and 2dB (return) losses in cruise tests

• Can still meet MER requirements if system has not degraded further

• Avoid last-minute surprises, time to re-plan if negative result

• Major challenges have been addressed

• Instrument FOV constraints

• Test in three phases

• Power-on test - does not involve Stanford - early June (completed)

• Nadir-point test (no attitude change) - late June

• Earth-point test - mid-August

• Project continues to work implementation details

• Scope/goals of each test

• Test timeline and scheduling of Stanford antenna

• Identification of backup opportunities

Mars Odyssey UHF System Test with Stanford

Likely Scenario for Earth-point test

• Test tentatively scheduled for ~ 25 Aug 2003

• Would perform one activity to point UHF at Earth

• Accommodates all S/C and instrument FOV constraints throughout

• ~10 minute slew to Earth-point attitude

• Dwell at Earth-point for ~20 minutes

• ~15 minute dogleg-slew to return to nadir-point

• Dogleg to avoid Mars in GRS cooler FOV during slew

• Would dedicate an orbit to this activity

• May possibly be repeated a few days later

• Will identify backup opportunity to perform test again a few weeks later

• Only re-test if necessary

Mars Odyssey UHF System Test with Stanford

Mars OdysseyOTM for Extended Mission

Plan for the Extended Mission:

• Perform an inclination-change maneuver to change the LST drift

• Propellant Budget Allocation: 1.9 kg (~10 m/s of V)

Design Constraints:

• Sun-synch at the earliest LMST that would provide a solar beta angle < -52.5˚ with 1.5˚ margin

• Margin analysis performed by ACS (D. Shafter)

• Any change/perturbation in orbit drift can be trended and accommodated by an OTM in the future if necessary

• To maintain Solar Beta Angle < -54.0˚ -> OTM ~Sept 23, 2003

Implementation

• Flight team has gone through one iteration of OTM design

• Attitude very close to nadir-point attitude

• Issue: Telecom during the burn

• If required: attitude change would negatively impact GRS

Mars Odyssey 5 PM Sun-Synchronous Orbit

All dates approximate

Mars Odyssey MER and Beagle2 UHF Relay

Landing Dates

• Beagle2: Dec 25, 2003

• MER-A: Jan 4, 2004

• MER-B: Jan 25, 2004

Impacts to Odyssey

• MER requested ODY orbit phasing to cover post-EDL deployments

• Assessing ability to predict/control orbit phasing

• Would likely alter the ground track repeat cycle

• UHF relay data requires change to packet buffer allocations

• Possibly in 2 stages, prior to relay, just prior to MER-B

• DSN allocations actually improve

• Nearly continuous downlink

• Lots of MSPA, sharing of uplink within a pass

Backup Slides

UHF RelayPacket Buffer Allocations

• Original Proposal (April 2002)

• Change GRS allocation from 30 MB to 12.5 MB allowed for 15 hours of data collection on-board Odyssey (assuming 1500 b/s collection with 30% margin)

Code 18 MB THEMIS 1 MB  1 GB (MMC)File System 10 MB GRS 30 MB 0 MBTHEMIS Scratch 40 MB MARIE 4 MB  80 MB

ODY Science 40 MB Attitude Recon

ODY Health + Sys Margin 7.5 MB THEMIS Engr

Relay 12.5 MB MARIE/GRS Engr128 MB Total 40 includes margin

Instr. Internal Memory

5 MB

Odyssey On-board Memory Allocations

Code 18 MB THEMIS 1 MB  1 GB (MMC)File System 10 MB GRS 12.5 MB 0 MBTHEMIS Scratch 40 MB MARIE 4 MB  80 MB

ODY Science 22.5 MB Attitude Recon

ODY Health + Sys Margin 7.5 MB THEMIS Engr

Relay 30 MB MARIE/GRS Engr128 MB Total 22.5 includes margin

Odyssey On-board Memory Allocations Instr. Internal Memory

5 MB

Mars Odyssey Onboard Memory Allocations (Apr 2002)

• Old Onboard Configuration (April 2002)

• Current On Board Configuration

• Proposed (New)

• Change GRS allocation from 30 MB to 8.5 MB allows for 12 hours of data collection on-board Odyssey (assuming 1500 b/s collection with 10% margin)

• Current average data rate of 990 bps equivalent to ~18 hours on board

Code 18 MB THEMIS 3.3 MB  1 GB (MMC)File System 10 MB GRS 30 MB 0 MBTHEMIS Scratch 40 MB MARIE 8.8 MB  80 MB

ODY Science 47.1 MB Attitude Recon

ODY Health + Sys Margin 7.5 MB THEMIS Engr

Relay 0 MB MARIE/GRS Engr122.6 MB Total 47.1 includes margin

Instr. Internal Memory

5 MB

Odyssey On-board Memory Allocations

Code 18 MB THEMIS 2.6 MB  1 GB (MMC)File System 10 MB GRS 8.5 MB 0 MBTHEMIS Scratch 40 MB MARIE 4.4 MB  80 MB

ODY Science 20.5 MB Attitude Recon

ODY Health + Sys Margin 7.5 MB THEMIS Engr

Relay 32.5 MB MARIE/GRS Engr128.5 MB Total 20.5 includes margin

Odyssey On-board Memory Allocations Instr. Internal Memory

5 MB

Mars Odyssey Onboard Memory Allocations (Current)

• Current Onboard Configuration

Mars OdysseyPacket Buffer Changes

• THEMIS Change from Original Baseline– Packet buffer allocation increased at the beginning of mapping due to 2 min. data

latency issue– Current allocation of 1500 packets (3.3 Mbytes) supports 110 kbps or 124 kbps– Reduction to 1200 packets (2.6 Mbytes) supports 110 kbps

• MARIE Change from Baseline– MARIE Changed from 40 file equivalent (2000 packets, 4.4 Mbytes) to 80 file

equivalent (4000 packets, 8.8 Mbytes)– Reduction in Frequency of MARIE Mode Changes Desired– Auto-Download Block Supports 80 file equivalent packet buffer– New 40 file Auto-Download Block Required

• MER/Beagle Packet Buffer Allocation (32.5 Mbytes Proposed)– 15 MBytes per MER supports 120 Mbits per pass (6820 packets)– 2.3 Mbytes for Beagle-2 supports 18.8 Mbits per pass (1050 packets)

Mars Odyssey2005 Average Daily Tracking Pass