FRR: Venus Proposal 13047
Flight Readiness Review (FRR):
Venus Proposal 13047
October 16, 2013
October 16, 2013
P. 1
FRR: Venus Proposal 13047
Agenda
1.0 Engineering Team
2.0 Introduction/Overview
2.1
2.2
2.3
2.4
(M. Slater, T. Roman,
C. Proffitt)
Objective
Statement of Adherence to AD 2-16 & AD 2-17
Background
On-Orbit History
3.0 FSW, S/C H/W Changes
and Implementation
3.1
3.2
3.3
3.4
3.5
3.6
(M. Slater) 5.0 Operations Activities/Installation
(N. Roy)
FSW and/or S/C H/W Functional Changes
FSW Software Structure/Resource Changes
CPM2 & 3 Update Recommendation
Supporting Ground System Changes
Supporting Documentation Changes
Release Messages
4.0 Testing and Verification
(N. Roy, J. Regalado)
4.1 Unit and Build Level Testing/Results
4.2 System Level Testing/Results
4.3 FSW/Operations Acceptance Testing, TSAR Status
and Results
4.5 H/W Interfaces Impact & Verification Matrix
4.4 Testing Liens and Limitations
4.6 Differences between Flight and Test Configurations
5.1
5.2
5.3
5.4
(J. Regalado,
M. Reinhart)
Overview and Initial Conditions
Ops Request and Script Review
Summary of SMS Observing Plans
Timeline Review – MEGG
6.0 Monitoring and System Impacts
6.1
6.2
6.3
6.4
6.5
6.6
(M. Slater)
On-orbit Validation / Monitoring
System Impacts
Supporting Operations Changes
Supporting PRD Changes
Supporting STScI Changes
Subsystem Training Module Changes
7.0 Constraints and Restrictions
Review
(M. Slater)
7.1 CARD
7.2 OLD
8.0 Contingency Planning
(M. Slater)
8.1 Vehicle Contingencies
8.2 Ground Contingencies
9.0 Engineering Support
Requirements
(M. Slater)
9.1 Personnel
9.2 Communications / Data
9.3 CCS Configuration
10.0 Liens/Forward Plan
October 16, 2013
(M. Slater)
P. 2
FRR: Venus Proposal 13047
1.0 Engineering Team
HST486
FSW
S. Benedict
S. Duhaney
N. Roy
Ron Stattel
B. Vreeland
FOT
J. Edwards
D. Grimes
B. Patel
D. Schaible
T. Walsh
Payload
FSW
D. Ehlers
C. Hoffman
M. Kelly
B. Serrano
C. Townsley
DMS/
I&C
J. Regalado
S. Sands
EPS/
TCS
D. Lewis
C. Proffitt
M. Reinhart
T. Roman
OTA
J. Stock
M. Wenz
PCS/
SAC
E. Kimmer
D. Murphy
Safing
E. Moy
SI
S. Arslanian
E. Graham
S. Swain
STScI
HITT
October 16, 2013
J. Atwell
S. Bozievich
VOCC
B. Smith
J. Smith
Sys
Mgmt
M. Slater
P. 3
FRR: Venus Proposal 13047
2.0 Introduction / Overview
2.1 Objective
• Perform observations associated with Venus Proposal 13047 –
“The D/H Ratio and Escape of Water from Venus” (PI: Clarke)
near the point of maximum eastern elongation, and load and
execute HST486 FSW macros bounding the observations.
2.2 Statement of Adherence to AD2-16 & AD2-17
• Testing and preparation for Venus Proposal 13047 followed the
guidelines of:
» AD 2-16 – “Operations Acceptance Testing”
» AD 2-17 – “Spacecraft Configuration Change Process”
October 16, 2013
P. 4
FRR: Venus Proposal 13047
2.0 Introduction / Overview
2.3 Background
• Objectives
» Explain Venus observing strategy
» Review areas of special concern with Venus observations and explain
how these concerns are being addressed
» Determine if implementation is correct and complete
• Why is Venus Special?
» At its maximum separation, Venus gets to be about 47° from the Sun
» HST is normally not permitted to point within 50° of the Sun
(Restriction 3.1.7.3)
• Scientific Goals
» Measure Lyman-alpha emissions from deuterium and from hydrogen in
order to determine the D/H ratio in the upper atmosphere
» To help distinguish between terrestrial and Venusian Lyman-alpha,
observations should happen when the Doppler shift from the combined
line of sight orbital motions of Venus and the Earth is maximized
» The Doppler shift requirement results in observing during the 2013
eastern elongation
October 16, 2013
P. 5
FRR: Venus Proposal 13047
2.0 Introduction / Overview
2.3 Background (Cont’d)
• Observing Strategy
» Observe while Venus is near maximum elongation
• 4 visits of 1 orbit each
» Observe while HST is in Earth’s shadow
• A window of 13-16 minutes per orbit
» Observe sky background near (~7°) from Venus but within HST’s
normal field of regard (i.e., >50°)
• 2 visits of 1 orbit each
» The visits may be scheduled in 6 consecutive orbits, but being
consecutive is not required
October 16, 2013
P. 6
FRR: Venus Proposal 13047
2.0 Introduction / Overview
2.3 Background (Cont’d)
• Observing Strategy Details
» Visits currently scheduled on October 24, 2013
» Scheduled in 6 consecutive orbits
» Order
1.
2.
3.
4.
5.
6.
October 16, 2013
Visit 03 – sky background
Visit 01 – Venus
Visit 02 – Venus
Visit 05 – Venus
Visit 06 – sky background
Visit 04 – Venus
P. 7
FRR: Venus Proposal 13047
2.0 Introduction / Overview
2.3 Background (Cont’d)
• Observing Strategy Details (Cont’d)
Target Visibility
Shadow
GS Pair
Slew to
Observe
Gyro Acq
Acq at
Venus
Venus
at
Venus+7°
Venus+7°
Observe
Single GS Acq
Slew to
Venus+7°
at Venus
Venus+7°
» Initial GS Acq at Venus+7°
•
•
•
•
October 16, 2013
A pointing 7° from Venus and 53.6° from the Sun
Minimizes slew distance to Venus
Precautionary measure to protect against large pointing error after slew
Provides additional sky background data
P. 8
FRR: Venus Proposal 13047
2.0 Introduction / Overview
2.3 Background (Cont’d)
• Observing Strategy Details (Cont’d)
Target Visibility
Shadow
GS Pair
Slew to
Observe
Gyro Acq
Acq at
Venus
Venus
at
Venus+7°
Venus+7°
Observe
Single GS Acq
Slew to
Venus+7°
at Venus
Venus+7°
» Single GS Acq at Venus
• Saves about a minute versus pair acquisition
» Venus science observation
• One 300s exposure
• STIS auto wave cal disabled
October 16, 2013
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FRR: Venus Proposal 13047
2.0 Introduction / Overview
2.3 Background (Cont’d)
• Venus Observation CAD Models/Geometries
» STIS 52x0.5 Slit on Venus in Visit 01
October 16, 2013
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FRR: Venus Proposal 13047
2.0 Introduction / Overview
2.3 Background (Cont’d)
• Venus Observation CAD Models/Geometries (Cont’d)
» HST’s View of Venus (t=0)
October 16, 2013
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FRR: Venus Proposal 13047
2.0 Introduction / Overview
2.3 Background (Cont’d)
• Venus Observation CAD Models/Geometries (Cont’d)
» HST’s View of Venus (t=0) (Cont’d)
• Bodies that are relevant to this observing program
Sun
Venus+7D Venus
October 16, 2013
P. 12
FRR: Venus Proposal 13047
2.0 Introduction / Overview
2.3 Background (Cont’d)
• Venus Observation CAD Models/Geometries (Cont’d)
» HST’s View of Venus (t=0) (Cont’d)
• Other bodies that happen to be appear in this view
Pluto
Mercury
Saturn &
moons
October 16, 2013
P. 13
FRR: Venus Proposal 13047
2.0 Introduction / Overview
2.3 Background (Cont’d)
• Venus Observation CAD Models/Geometries (Cont’d)
» HST’s View of Venus (t=0) (Cont’d)
• At about this time, HST is beginning its slew from Venus+7D to Venus
October 16, 2013
P. 14
FRR: Venus Proposal 13047
2.0 Introduction / Overview
2.3 Background (Cont’d)
• Venus Observation CAD Models/Geometries (Cont’d)
» HST’s View of Venus (t=5m)
• Slew to Venus is continuing. Sun is about to set.
terminator
Earth
October 16, 2013
P. 15
FRR: Venus Proposal 13047
2.0 Introduction / Overview
2.3 Background (Cont’d)
• Venus Observation CAD Models/Geometries (Cont’d)
» HST’s View of Venus (t=10m)
• Sun has set. Slew to Venus is complete. GS Acq. is in progress.
October 16, 2013
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FRR: Venus Proposal 13047
2.0 Introduction / Overview
2.3 Background (Cont’d)
• Venus Observation CAD Models/Geometries (Cont’d)
» HST’s View of Venus (t=15m)
• Science observation is beginning
October 16, 2013
P. 17
FRR: Venus Proposal 13047
2.0 Introduction / Overview
2.3 Background (Cont’d)
• Venus Observation CAD Models/Geometries (Cont’d)
» HST’s View of Venus (t=20m)
• Science observation is continuing
October 16, 2013
P. 18
FRR: Venus Proposal 13047
2.0 Introduction / Overview
2.3 Background (Cont’d)
• Venus Observation CAD Models/Geometries (Cont’d)
» HST’s View of Venus (t=25m)
• Science observation is complete. Slew away from Venus is in progress.
October 16, 2013
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FRR: Venus Proposal 13047
2.0 Introduction / Overview
2.3 Background (Cont’d)
• Venus Observation CAD Models/Geometries (Cont’d)
» HST’s View of Venus (t=30m)
• Slew away from Venus is complete. Pointing at Venus+7D with gyro
guiding.
October 16, 2013
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FRR: Venus Proposal 13047
2.0 Introduction / Overview
2.3 Background (Cont’d)
• Venus Appearance at Observation
» Apparent V magnitude: -4.5 ± 0.3
» Apparent diameter: 23.0”
» Phase angle: 86.3°
• STIS Bright Object Screening
» Observations will use STIS E140H Cenwave=1234 Å with 52x0.5
aperture
» Allowed count rate screening limits
• No more 200,000 counts/second global rate
• No more than 75 counts/pixel/second locally
October 16, 2013
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FRR: Venus Proposal 13047
2.0 Introduction / Overview
2.3 Background (Cont’d)
• STIS Bright Object Screening (Cont’d)
» Expected count rates
• Previous observations with other satellites give Venus Lyman-alpha
surface brightness of ~20 kR = 6e-13 ergs/cm2/s/arc-sec2 with line width
of ~1 Å
• ETC calculation (STIS.sp.538741) for 0.2x0.2 aperture predicts only
4 c/s global rate from source and 0.02 c/p/s local
– Scaling to 0.5” wide slit x 12” (half illuminated disk of Venus) yields
a predicted global rate of 625 c/s with peak local rate of ~0.05 c/p/s
• January 2003 Venus observations from Program 8069 using E140H
Cenwave=1234 Å with 0.2x0.09 aperture saw only 0.25 c/s from
combined geo-coronal + Venusian Lyman-alpha
– No evidence of any continuum spectrum from Venus was visible
– Current program will observe 12”x0.5” area of illuminated disk
(~350x larger) which would give only 100 c/s global count rate if
scaled from the smaller aperture used by the earlier program
– The small area of the aperture used by Program 8069 may well
have missed localized emission
» Comparison between expected vs. allowed count rates
• 625 c/s global << 200,000 c/s allowed global screening rate
• 0.05 c/p/s local rate << 75 c/p/s allowed local screening rate
October 16, 2013
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FRR: Venus Proposal 13047
2.0 Introduction / Overview
2.3 Background (Cont’d)
• STIS Bright Object Screening (Cont’d)
» Also need to check for bright background objects
• O5 star with V=10 would be close to allowed global limit of 200,000 c/s
• When comparing with the field, the parallax effects due to HST’s orbital
motion need to be included
– Shift in position over HST orbit similar to the angular size of Venus
(~23”)
• Procedure:
– The program coordinator provided to the instrument scientist with
HST-centric ephemerides for both the Venus and Venus-OFFSET7D target pointings
– Current bright object tool was used to check fixed pointings spaced
at 10 min intervals along the target path to clear the region swept
out by the MAMA observations
October 16, 2013
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FRR: Venus Proposal 13047
2.0 Introduction / Overview
2.4 On-orbit History
• In 1995, Proposals 4518 (PI: Esposito) and 5783 (PI: Esposito)
performed Goddard High Resolution Spectrograph (GHRS) and
Wide Field Planetary Camera 2 (WFPC2) observations of Venus
near maximum western elongation.
• In 2003, Proposal 8659 (PI: Bullock) performed STIS
observations of Venus near maximum western elongation.
• In December 2010/January 2011, Proposal 12433 (PI: Jessup)
performed STIS CCD observations of Venus near maximum
western elongation
• These October 2013 Proposal 13047 (PI: Clarke) STIS MAMA
observations are near maximum eastern elongation
October 16, 2013
P. 24
FRR: Venus Proposal 13047
3.0 FSW, S/C H/W Changes and Implementation
3.1 FSW and/or S/C H/W Functional Changes
• Venus Observation SPC Macros (DCR 1637)
» Load File – QVENUS0_0.TAB
• Contains 2 macros
» Venus Observation Macro at SPC Address 17555 (Jump Table Addr 1)
• Perform BMIC management for the modified tables
• Modify the Sunpoint Sun Cosine Limit from 46 to 42 degrees
• Modify six safe test responses from Inertial Hold to Software Sunpoint (w/o
Load Shed)
– SBREHE – High Mode Body Rate Error
– SSPCLEXE – SPC List Exhaust
– SBMICE – BMIC
– SEMBOPE – Earth-Moon Protection
– SMHGATCT – HGA Torque Limit
– SNELEAKE – Neon Leak Test
• Other Inertial Hold test responses close the aperture door (AD) in addition to
IH and are not changed in macro (HST is thermally safe if the AD is closed
and Sun angle is 46 degrees)
– SPSEAPSE – PSEA Power Supply Failure
– SSUNAPRE – Sun Aperture
– SSBOPE – Sun Bright Object Protection
October 16, 2013
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FRR: Venus Proposal 13047
3.0 FSW, S/C H/W Changes and Implementation
3.1 FSW and/or S/C H/W Functional Changes (Cont’d)
• Venus Observation SPC Macros (DCR 1637) (Cont’d)
» Post-Venus Observation Macro at SPC Address 17601 (Jump Table
Addr 2)
• Perform BMIC management for the modified tables
• Restore the Sunpoint Sun Cosine Limit from 42 to 46 degrees
• Restore six safe test responses from Software Sunpoint to Inertial Hold
» Installation and Usage Procedure
“IP-248_Venus_Observation_Macros.docx”
• 3 Sections
– Load, dump and compare QVENUS0_0.TAB, to verify the load
– Execute the Venus Observation Macro as required
– Execute Post-Venus Observation Macro as required
October 16, 2013
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FRR: Venus Proposal 13047
3.0 FSW, S/C H/W Changes and Implementation
3.2 FSW Software Structure/Resource Changes
• None.
3.3 CPM2 & 3 Update Recommendation
• N/A
3.4 Supporting Ground System Changes
• None.
3.5 Supporting Documentation Changes
• None.
3.6 Release Messages
• SSM232
• IP-248_Venus_Observation_Macros.docx
• PNM_2013262192058.TXT
October 16, 2013
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FRR: Venus Proposal 13047
4.0 Testing and Verification
4.1 Unit and Build Level Testing/Results
• 1 FVS Test – List Exhaust with response changed to SWSP by the
macro and Sun Protection Test fails with modified limit, closing the
aperture door
• Macro contents verified by inspection
» Macros use the same symbols but with Venus and restored values,
respectively
4.2 System Level Testing/Results
• Software Simulation Environment
» 2 FVS tests were run to verify the proper configuration after macro execution
• VENOBS1 – Venus Observation Test 1 – Nominal Case
• VENOBS2 – Venus Observation Test 2 – SPC List Exhaustion
– Tested that Software Sunpoint is commanded versus Inertial Hold
• Hardware Test Environment
» Lab Configuration
• CCS 8.3.0.0.23 / PRD D07756S
• PCSSIM 54A
• On-Orbit patches installed
• Gyro 6-4-5
» Installation Procedure Verification using VSSNOR and IP-248
• Completed in 486 Lab
October 16, 2013
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FRR: Venus Proposal 13047
4.0 Engineering Test / Installation
4.3 FSW/Operations Acceptance Testing, TSAR Status and
Results
• VEST Configuration for October 3, 2013 (Day 276):
» Ground system software – CCS Version 8.4.0.0.12
» CCS string – H Test
» Database – PRD-O07700ST
• Quick update of QFSW37ARAM2.tcl proc applied
»
»
»
»
»
NSSC-1/CDH2 FSW 9.2.2
STIS Ops Bench
PSEA
SSR-1
PCS SIM Version 54A
• 486 FSW Configuration (current on-orbit)
»
»
»
»
»
October 16, 2013
FSW 3.7A installed
BMIC enabled
KA enabled
Telemetry format HN
Safemode tests and macros enabled
P. 29
FRR: Venus Proposal 13047
4.0 Engineering Test / Installation
4.3 FSW/Operations Acceptance Testing, TSAR Status
and Results (Cont’d)
• Test Sequence:
» Executed IP-248 – “Venus Observation Macros Installation and
Usage Procedure”, Section A to load, dump, and compare the
Venus Observation SPC Macros
» Executed IP-248 – “Venus Observation Macros Installation and
Usage Procedure”, Section B to activate Macro 1 (i.e., the Venus
Observation Macro)
• Modifies six safe test responses from Inertial Hold to Software Sunpoint
• Changes the Sun Cosine Limit from 46° to 42°
» Monitored Venus Observation
• All guide star acquisitions performed as expected
• STIS observations were both recorded and collected in real-time for
Payload FSW verification of timestamps within science data headers
» Executed IP-248 – “Venus Observation Macros Installation and
Usage Procedure”, Section C to activate Macro 2 (i.e., the PostVenus Observation Macro)
• Restores safe test responses and the Sun Cosine Limit to their nominal
values
October 16, 2013
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FRR: Venus Proposal 13047
4.0 Engineering Test / Installation
4.3 FSW/Operations Acceptance Testing, TSAR Status
and Results (Cont’d)
• HSTAR and TSAR Status
HSTAR
Title & Description
Assignee
Resolution
Status
13826
Multiple Data Dropouts on H-string
FEP – H-string VLANs 218 and 228
were being scanned
System
Admin
Resolved during the OAT by
recycling the H-string
Open
TSAR
Title & Description
Assignee
Resolution
Status
4146
Response team could not access
STScI test machines for PNM
transfer – Password had been
changed
CCS
The OAT products were
manually transferred. CCS is
obtaining a new account from
the STScI.
In
Analysis
4147
Plot Freeze within FGS Pickles
Display – FGS pickles displays on
both VOCC and H-String froze
before return to FGS default
CCS
Resolved to CR 10256.
Workaround: Close/reopen
Pickles display between guide
star acqs. Use of this display is
not critical to the activity.
Resolved
4148
STK/CCS on PCS STK workstation,
OSRS03 not working – Symantec
blocked CCS from coming up due to
JAVA versions
Network
The workstation was tested
following the OAT with no
problems. Use of STK is not
critical to the activity.
Open
October 16, 2013
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FRR: Venus Proposal 13047
4.0 Engineering Test / Installation
4.3 FSW/Operations Acceptance Testing, TSAR Status
and Results (Cont’d)
• HSTAR and TSARs did not prevent the execution of the test
script or impact the test results
• Summary
 The Venus Observation Macros loaded and executed as expected
• No operations procedures were modified as a result of the test
 The SMS executed successfully through the Venus visit
• No significant changes to stored commanding or proposals were
required
• Attitude for Venus observation was as expected
• Exposure timing was as expected
– Payload FSW verified timestamps within the headers of the
dumped STIS MAMA images
October 16, 2013
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FRR: Venus Proposal 13047
4.0 Testing and Verification
4.4 H/W Interfaces Impact & Verification Matrix
• HST486 FSW
DCR’s
FVS TESTS
486LAB and/or DSTIF
TESTS
RESULTS
1637
2 – VENOBS1
VENOBS2
VSSNOR/IP-248
All Passed
4.5 Testing Liens and Limitations
• The Venus observation attitudes are hot for the telescope baffles
since the +V1 axis is pointed ~46.8° away from the Sun
» Hardware temperatures are not modeled within the test environment
» TCS has completed their analysis of the observing plan and has
confirmed that the light shield baffle temperatures will remain well
below the 300°F threshold cited within Constraint 2.2.1.7 – “OTA
Light Shield Baffle Thermal Limits” (email dated September 17,
2013)
October 16, 2013
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FRR: Venus Proposal 13047
4.0 Engineering Test / Installation
4.6 Differences Between Test and Flight Configurations
• No NSSC-1 FSW image was loaded in the HST486
» There was no need to reload the NSSC-1 FSW during the test
» No impact
• The test SMS contained only two acquisitions for one Venus visit
to be used in the operational SMS (i.e., a pair acq. and an
associated single star acq.)
» The four Venus visits are effectively identical with only slight
differences in the pre-Venus background exposure times and the
positions of Venus itself
» The two background visits are typical STIS MAMA observations
» No impact
October 16, 2013
P. 34
FRR: Venus Proposal 13047
5.0 Operations Activities/ Installation
5.1 Overview and Initial Conditions
• SSM486 Flight Software Version 3.7A or higher is installed and
executing in VSS with H-format programmable telemetry enabled
• Load and execute the Venus Observation macros bounding the
Venus visits
5.2 Ops Request and Script Review
• Section A – Load, dump, compare Venus Observation SPC Macro
Table Load
» Load Venus Observation SPC Macro Table load (1 min)
» Dump SPC Table 1 (5 min)
» Compare the load and dump images (1 min)
• Section B – Venus Observation Macro Activation
» Activate Venus Observation Macro (i.e., Macro 1) (1 min)
• Monitor Venus observations
• Section C – Venus Observation Restoration
» Verify special processor not active (1 min)
» Activate Post-Venus Observation Macro (i.e., Macro 2) (1 min)
October 16, 2013
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FRR: Venus Proposal 13047
5.0 Operations Activities/ Installation
5.3 Summary of SMS Observing Plans
• GS Acq. Adjustments
» Visit 03 – sky background
• 297/11:24:50 – Pair: No Changes
» Visit 01 – Venus
• 297/12:46:52 – Pair: No Changes
• 297/13:28:18 – Single: AQEXPIRE from 780s to 1800s
» Visit 02 – Venus
• 297/14:19:18 – Pair: Allow for 55” search due to suppressed OBAD
• 297/15:03:41 – Single: AQEXPIRE from 780s to 1800s
» Visit 05 – Venus
• 297/15:55:28 – Pair: No Changes
• 297/16:39:15 – Single: AQEXPIRE from 780s to 1800s
» Visit 06 – sky background
• 297/17:30:48 – Pair: No Changes
» Visit 04 – Venus
• 297/19:06:51 – Pair: No Changes
• 297/19:51:09 – Single: AQEXPIRE from 780s to 1800s
» The AQEXPIRE changes ensure that the timer will expire well after the timer’s
termination by the PCPTERM at the start of the slew away from Venus
• This prevents any possibility of the GSACQ failing and the expire timer stepping on
the activities to slew away from Venus
October 16, 2013
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FRR: Venus Proposal 13047
5.0 Operations Activities/ Installation
5.4 Timeline Review
• Operations Request 19500 – “Venus Observation”
» Start time 297/11:03 UTC (October 24 @ 7:03 am. EDT)
» Load, dump and compare Venus SPC macros and activate Macro 1
• First opportunity @ 297/11:03 – 11:33
• Second opportunity @ 297/11:45 – 12:36
• Third opportunity @ 297/12:38 – 13:12
» Last slew out from Venus @ 297/20:12
» Activate Macro 2
• First opportunity @ 297/20:16 – 21:08
• Second opportunity @ 297/21:19 – 21:39
• Third opportunity @ 297/22:00 – 22:50
October 16, 2013
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FRR: Venus Proposal 13047
5.0 Operations Activities/ Installation
GS Pair Acq @ Venus +7d
October 16, 2013
1st op. to load, dump and compare SPC macro &
Activate Macro 1
2nd Opportunity
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FRR: Venus Proposal 13047
5.0 Operations Activities/ Installation
GS Pair Acq @ Venus +7d
Single GS Acq @ Venus
1st slew inside of the 50d SAZ
3rd Opportunity
October 16, 2013
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FRR: Venus Proposal 13047
5.0 Operations Activities/ Installation
Single GS Acq @ Venus
GS Pair Acq @ Venus +7d
October 16, 2013
GS Pair Acq @ Venus +7d
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FRR: Venus Proposal 13047
5.0 Operations Activities/ Installation
Single GS Acq @ Venus
October 16, 2013
GS Pair Acq @ Venus +7d
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5.0 Operations Activities/ Installation
GS Pair Acq @ Venus +7
October 16, 2013
Single GS Acq @ Venus
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5.0 Operations Activities/ Installation
1st op. to activate Post-Venus
Observation macro 2
October 16, 2013
2nd Opportunity
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FRR: Venus Proposal 13047
5.0 Operations Activities/ Installation
3rd Opportunity
October 16, 2013
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FRR: Venus Proposal 13047
6.0 Monitoring and System Impacts
6.1 On-Orbit Validation / Monitoring
• DMS and FSW will validate the successful load of the macros
• DMS will verify macro execution
6.2 System Impacts
• DMS/I&C – MAT LEI suspended from 297/11:00 to 22:52 UTC
• OTA –
» GS Acq. parameters modified for Venus visits
» OTA signoff of SMS required
• SAF – Temporary modification to responses of six safemode tests
and to Sun bright object protection threshold
» PSEA BOD circuitry provides hardware protection in the event that the
Sun is within 38° of the boresight
• TCS – Waiver required for Restriction 3.1.7.3 – “HST Sun Pointing
Limits”
• STScI – GS Acq. parameters modified for Venus visits
• EPS, FOT, FSW, PCS, SI – None
• SAMS, HSTGS Development and Response Teams, Test Systems
– None
• Critical Science Considerations – N/A
October 16, 2013
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FRR: Venus Proposal 13047
5.0 Monitoring and System Impacts
6.3 Supporting Operation Changes
• None.
6.4 Supporting PRD Changes
• None.
6.5 Supporting STScI Changes
• None.
6.6 Subsystem Training Module Changes
• None.
October 16, 2013
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FRR: Venus Proposal 13047
7.0 Constraints and Restrictions Review
7.1 CARD
• No operations constraints or restrictions are violated and no waivers are
required during macro installation
» All installation activities are handled by FSW installation procedure
• Restriction 3.1.7.3 – “HST Sun Pointing Limits” must be waived for
execution of the Venus Observation Macro
» TCS has completed their analysis of the observing plan and has confirmed that
the light shield baffle temperatures will remain well below the 300°F threshold
cited within Constraint 2.2.1.7 – “OTA Light Shield Baffle Thermal Limits” (email
dated September 17, 2013)
» The Sun Cosine Limit is being reduced from 46° to 42° during the Venus
observation period to provide ~4° margin relative to the expected 46.8° Sun
angles
• Constraints 2.4.9.1 – “STIS MAMA Global Bright Object Limits” and 2.4.9.2
– “STIS MAMA Local Bright Object Limits”, although relevant, will not be
violated.
» Venus is not nearly as bright in the FUV as it is in the Visual
» Bright scene detection and the local rate monitor will remain enabled
• All contingency procedures comply with the CARD
7.2 OLD
• No operations limitations are violated and no waivers are required
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FRR: Venus Proposal 13047
8.0 Contingency Planning
8.1 Vehicle Contingencies
• Loss of communication with HST while loading the macros or
executing the macros
» Continue procedure at next opportunity
• SI C&DH safing event
» The Venus and Post-Venus observation macros will be loaded and
executed as planned
» The HST486 SMS will continue to execute
» Venus observation science data will not be collected
» The SI C&DH will be restored to its nominal state in accordance
with established procedures
» The STScI may reschedule the observations
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FRR: Venus Proposal 13047
8.0 Contingency Planning
8.1 Vehicle Contingencies
• HST safing while pointed within the Solar Avoidance Zone (SAZ)
» Concern
• If HST were to enter inertial hold safe mode while pointed within the SAZ,
Constraint 2.2.1.7 – “OTA Light Shield Baffle Thermal Limits” could be
violated
» Precautions
• Six safe test responses will be temporarily modified from Inertial Hold with
the Aperture Door open to Software Sunpoint (w/o load shed) to prevent
prolonged Sun exposure
– This was done for all prior HST observations of Venus
• Three opportunities are planned for execution of Macro 1 prior to the slew
into Venus
• Macro 1 isn’t executed prior to the first slew into Venus
» Concern
• The protections mentioned above are not in place
» Precautions
• Macro 1 will be executed at the next opportunity during the Venus visit period
• If the vehicle enters inertial hold inside of the SAZ, then software sunpoint
will be manually commanded via COP 6.01 (Ops Request 19497-2 –
“CONTINGENCY: Commanding SWSP during Venus Observation”)
• MAT LEI has been suspended throughout the Venus visit period
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FRR: Venus Proposal 13047
8.0 Contingency Planning
8.1 Vehicle Contingencies (Cont’d)
• HST in the Sun
» Concern
• While slewing to Venus, HST will be exposed to sunlight and pointed
inside the SAZ for up to 0m 55s
• HST’s maximum previous exposure to sunlight while pointed inside the
SAZ was 3m 12s (Jan 2011)
• Pointing inside the SAZ while HST is in sunlight can be tolerated for at
least 15 minutes before the temperature of the paint inside the OTA
would exceed 250°F and become a contamination issue
(EM-MOSES-1067 and EM-MOSES-1268)
• TCS evaluated the variables that contribute to hot light shield baffle
temperatures for the observing plan and confirmed that the observations
pose no threat of contamination from outgassing (email dated
September 17, 2013)
– Sunlit duration while inside the SAZ is well below the 15 minute
outgassing point
– Solar intensity is shorter than the previous Venus observation
resulting in cooler temperatures
– Sun angle is similar to/slightly larger than previous Venus
observation
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FRR: Venus Proposal 13047
8.0 Contingency Planning
8.1 Vehicle Contingencies (Cont’d)
• HST in the Sun (Cont’d)
» Vital Statistics – Prior Venus Observations
Science
Exposure
Time
Angle to
Sun Limb
(degrees)
Sunlit Time inside SAZ
While Slewing Away
from Venus
January 1995
22-109s
per orbit
46.3
2m 20s
January 2003
255s
46.0
2m 30s
Dec 28, 2010 orbit 1
153s
46.2
2m 14s
S924000129 in FGS1
on centerline
Dec 28, 2010 orbit 2
153s
46.2
3m 1s
S924000129 in FGS1
~50” from centerline
Jan 22, 2011 orbit 1
58s
46.1
1m 57s
S8OF000650 in FGS1
12” from centerline
Jan 22, 2011 orbit 2
58s
46.1
1m 50s
S8OF000650 in FGS1
on centerline
Jan 27, 2011 orbit 1
120s
45.7
3m 12s
S8L2000017 in FGS1 36”
from centerline
Jan 27, 2011 orbit 2
120s
45.7
3m 2s
S8LA045471 in FGS2 29”
from centerline
Observation
October 16, 2013
Guide Star
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FRR: Venus Proposal 13047
8.0 Contingency Planning
8.1 Vehicle Contingencies (Cont’d)
• HST in the Sun (Cont’d)
» Vital Statistics – October 24, 2013
Observation
Science
Exposure
Time
Angle to
Sun Limb
(degrees)
Sunlit Time inside SAZ
While Slewing Toward
Venus
Visit 01
5m (i.e., 300s)
46.6
0m 14s
S8G1000134 in FGS1
<= ~70” from centerline
Visit 02
5m
46.6
0m 36s
S8G1000134 in FGS1
<= ~60” from centerline
Visit 04
5m
46.6
0m 28s
S8G1000147 in FGS1
<= ~45” from centerline
Visit 05
5m
46.6
0m 55s
S8G1000134 in FGS1
<= ~60” from centerline
Guide Star
» Total time pointed in SAZ (sunlit & shadow) is 20-21 minutes per
orbit.
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8.0 Contingency Planning
8.1 Vehicle Contingencies (Cont’d)
• FGS exposure to Venus
» Concern
• The FGS photo-multiplier tubes may be exposed to bright light if large
attitude errors (>300 arcsec) allow the FGS to see Venus
» Precautions
• The guide stars for the single star acquisitions are angularly separated as far
as possible from Venus and are in FGS1 (farthest from STIS)
– Bad OBADs will be very unlikely to put Venus within the FGS’s guide
star search radius
– S8G1000134 – ~870”, ~927”, and ~1046” from Venus on Orbits 2, 3,
and 4, respectively
– S8G1000147 – ~956” from Venus on Orbit 6
• The guide stars for the single star acquisitions have been used on orbit
» Analysis
• Goodrich assessed potential PMT damage for a worst-case event resulting
in an attempted acquisition of Venus (ref: Goodrich Memo A16-ST-2254)
– The immediate effect of the attempted Venus acquisition would be the
temporary incapacitation of the PMTs due to dark count elevation from
several to up to 48 hours
– The long term effect of the attempted Venus acquisition could be a
decrease in reliability from 1-3% depending on how long Venus resides
in the FGS’s FOV
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FRR: Venus Proposal 13047
8.0 Contingency Planning
8.1 Vehicle Contingencies (Cont’d)
• Guide Star Acquisition Failure
» Concern
• If attitude error is greater than the search radius, the guide star
acquisition could fail resulting in the loss of the science
» Precautions
• The chances are minimized by the short 7 degree slew to Venus
• Perform guide star acquisition test before the Venus observing
timeframe
– Tests occurred on September 17 and September 18
– Both were successful
8.2 Ground Contingencies
• Loss of communication with HST
» Continue procedure at next opportunity
• Loss of primary CCS string during activity
» Switch to backup string and resume activity
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FRR: Venus Proposal 13047
9.0 Engineering Support Requirements
9.1 Personnel
•
•
•
•
•
Test Conductor – J. Regalado in MOR/OSR
NASA OM – M. Myslinski
486 FSW, PCS, and Sys Mgmt – N. Roy, J. Germany, M. Slater in OSR
EPS, I&C, OTA, P/L FSW, Safing, SI, and TCS – on-call
FOT – J. Edwards/D. Grimes (am.) & D. Schaible/T. Walsh (pm.) in MOR
9.2 Communications / Data
• Circuit assignments:
» R/T OPS COORD – Primary circuit for Test Conductor and Shift Supervisor
• SMS – OTA signoff is required
• Operations Requests (OR’s):
» 19500-0 – “Venus Observation”
» 19497-2 – “CONTINGENCY: Commanding SWSP during Venus Observation”
• Flash Reports will be issued following:
» Macro loads
» Macro 1 execution
» Macro 2 execution
• FRR material is available on EDOCS web site
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FRR: Venus Proposal 13047
9.0 Engineering Support Requirements
9.3 CCS Configuration
• CCS Strings
» Prime Ops on F-String – CCS 8.4.0.0.12
» Back-up Ops on D- and H-Strings – CCS 8.4.0.0.12
• OPS PRD O07700S
• 486 FSW loads transferred in accordance with AD 2-04
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10.0 Liens/Forward Plan
Liens
• None
Forward Plan
• N/A
October 16, 2013
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Backup Material
October 16, 2013
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FRR: Venus Proposal 13047
Backup Material
TCS Analysis for October 2013 Venus Observation
From: Lewis, Deneen
Sent: Tuesday, September 17, 2013 3:54 PM
To: Haskins, David N; Myslinski, Mike; Lupie, Olivia L.
Cc: Smith, Daniel C.; Dunham, Larry; Slater, Mark A.; Crabb, Bill; Waldo, Greg; Krol, Stan; Setty,
Amar O; Wenz, Mike
Subject: TCS Analysis for October 2013 Venus Observation
All,
For the TCS analysis for planned October 2013 Venus Observation, EM: MOSES 1067 (Light
Shield Thermal Analysis for Venus Observations) was reviewed. This EM addresses the concern of
a direct solar load striking the HST light shield internal baffles, located inside the aperture, resulting
in temperatures approaching 300 degF. Black paint on the baffles is prone to outgassing when
temperatures exceed 250 degF resulting in potential contamination of the primary and secondary
mirrors. Further studies performed in 2004 concluded that the outgassing range could be extended
to 300 degF. The data and observations from the EM MOSES 1067 analysis and the study in 2004
were compared to the upcoming October 2013 Venus observation to confirm compliance with
CARDs 2.2.1.7 and 3.1.7.3. This comparison will serve as the basis for the TCS analysis as there is
no HST thermal flight telemetry (baffle temperature monitors) in the area of the direct solar load.
Analysis documented in EM: MOSES 1067 indicate that the peak baffle temperature reached 220
degF with HST configured in the Venus Observation attitude (46.3 degrees from the +V1 axis sun
angle) over a single orbit and the sun illuminating inside the aperture for seven minutes. After 15
minutes the temperatures exceeded 250 degF.
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Backup Material
TCS Analysis for October 2013 Venus Observation (Cont’d)
Additional analysis with a configuration similar to the proposed October 2013 Venus Observation
showed that the peak baffle temperature reached 171 degF with HST configured in the Venus
Observation attitude for three consecutive orbits and the sun illuminating inside the aperture for two
minutes each orbit (reference plot from EM MOSES 1067 below). Again, after 15 minutes the
temperatures exceeded 250 degF. Both analyses conclude that pointing inside the aperture while
HST is in sunlight can be tolerated for at least 15 minutes without the temperature of the black paint
on the baffles causing contamination issues.
October 16, 2013
(Baffles)
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Backup Material
TCS Analysis for October 2013 Venus Observation (Cont’d)
(Shroud)
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Backup Material
TCS Analysis for October 2013 Venus Observation (Cont’d)
The October 2013 Venus Observation proposal consists of visits scheduled over six consecutive
orbits with HST configured with the sun pointed 46.6 degrees from the +V1 axis and the sun
illuminating inside the aperture for a maximum of 1 minute 35 seconds. Note, HST’s maximum
previous exposure to sunlight was 3 minutes 12 seconds (January 27, 2011). Although, CARD
3.1.7.3 (HST Sun Pointing Limits) will require a waiver since HST line-of-sight will be pointed closer
than 50 degrees to the sun, per the EM MOSES 1067 data CARD 2.2.1.7 (OTA Light Shield Baffle
Thermal Limits) is satisfied as the baffle temperatures will not exceed 250 degF with sunlight
exposure much shorter than 15 minutes. CARD 2.2.1.7 protects for light shield baffle temperatures
exceeding 300 degF. Also, the solar intensity is lower in October than the December-January
timeframe resulting in cooler temperatures overall.
With a similar configuration as the EM analysis coupled with shorter sun exposure durations and
lower sun intensity, TCS SE confirms the configuration can be tolerated as it poses no threat of
contamination.
Deneen Lewis
Electrical Power Systems Engineer
Jackson & Tull Engineers, Hubble Space Telescope Program
Goddard Space Flight Center
301-286-3481
October 16, 2013
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