The Triana observatory was built at NASA GSFC in the late 1990's, then placed into storage. After approximately ten years it was removed from storage and repurposed as the Deep Space Climate Observatory (DSCOVR). This presentation outlines the contamination control program lessons learned during the integration, test and launch of DSCOVR

Graziani, Larissa

NASA Technical Reports Server

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Contamination, Coatings, Materials and Planetary Protection Conference
NASA Goddard Space Flight Center
July 2015
DSCOVR Contamination Lessons Learned
Larissa Graziani
https://ntrs.nasa.gov/search.jsp?R=20150017744 2019-08-31T06:18:39+00:00Z
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• Triana was developed in the late 1990’s as a quick-build small 
explorer carrying five instruments on a NASA-based mission.
• Primary mission was Earth science via a visible-band camera and 
infrared radiometer. Space weather (magnetometer, electron 
spectrometer, Faraday cup) was secondary science.
• Observatory was slated for L1 orbit, oriented to permanent Earth and 
sun views. 
• Manifested for a shuttle. Later removed from manifest to 
accommodate ISS build. 
• Placed into storage after completing thermal vacuum test in Fall 2001
• Briefly removed from storage on two occasions. Permanently 
removed from storage in 2012 to become a NOAA-based mission.
• NOAA and NASA rededicate the spacecraft as DSCOVR. Space 
weather to be DSCOVRs primary mission. 
• Spacecraft dismantled to box level for component testing. 
• Repeated environmental tests.
• Launched on a Space X Falcon 9 in February 2015. 
Background: Triana to DSCOVR
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Triana in 2001
Then and Now: Changes Made
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DSCOVR in 2015
Electron Spectrometer 
moved from boom to 
spacecraft bus
Magnetometer placed 
on angled cone at end 
of boom
Camera and radiometer MLI 
outer layers changed from 
ITO-coated Kapton to 
Germanium-coated Black 
Kapton (GBK)
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• Triana was double bagged and placed in a 
metal container. Container was placed in a 
cleanroom and purged with nitrogen.
• Some GSE was dispersed to functional groups
• Most GSE was boxed and placed in 
warehouse storage. 
• Documents and drawings that were in 
configuration management control were 
maintained well. Background information 
under personal or vendor control was 
sometimes lost. 
Storage of Hardware and Information
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• CC group retained all 
bakeout data and 
reports from Triana
• In future, request data 
stored by vendors as 
deliverables
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• Needed to evaluate materials list for limited-life items
– Lubricants were biggest concern
– All were considered still usable
• Needed to review parts list for items with known problems as reported 
through industry alerts
– Some electronics parts had been flagged a few years earlier
– Flight battery determined to be unusable. Changed to a new Lithium Ion 
battery, which required some mechanical modifications to the bus
– Thermal control surfaces looked fairly good upon first look
• Some dark spots seen on Silver Teflon and GBK surfaces. Measured within 
thermal specification
• White paint still within thermal specifications and adhering well
• Conductivity of surfaces needed to be evaluated
• Boom removed, deployed and inspected
– Saw some slight splintering on fiberglass struts
– Mild paint wear was touched up with Z306
– No major work needed. Were able to re-install and fly
• All mechanisms thoroughly tested
Unpacking
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• Most thermal control surfaces degraded quickly with handling
• NS43C paint powdered throughout I&T; repaired with Z93C55
• Germanium flaked from some tape surfaces
• High temperature MLI frayed at edges; backed with SS mesh to strengthen
• Phosphoric-acid etched nickel inside radiometer began flaking. Stripped and 
recoated with Z306
• ITO conductivity questioned, noticeable cracks seen on some surfaces. ITO 
Kapton outer layer replaced with GBK layer
• All produced conductive particles, which were a problem for the high-voltage 
Faraday Cup
• Root cause not clear: time alone, too dry for too long or a combination
Thermal Control Surfaces
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Y Budgets and Modeling
• Needed to take a fresh look at the contamination budget and 
verification methods.
– A new approach may have developed in intervening years.
– For DSCOVR, budget was only slightly modified to reflect better 
understanding of instrument sensitivities.
– Needed to upgrade magnetic cleanliness procedures
• Updated all contamination models
– Knowledge of thruster plume shape and behavior advanced while 
Triana/DSCOVR sat in storage
• Thruster plume shape in model changed from cone to tear drop
• Better and more complete information on exit gas properties
– Thruster plume model was no longer considered valid and needed to be 
redone
– On-orbit molecular transport model still valid. Only needed update to 
account for move of spectrometer and magnetometer
– Need to know assumptions and parameters to evaluate the models. 
Data retention from Triana days was key.
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Y Purge 
• GSE-disconnect purges on camera, radiometer, faraday cup, 
electron spectrometer
• Purge would have been easier to use as a T-0 disconnect
– Drag-on system designed for shuttle
– Purge connection points had aged poorly and were difficult to replace
– Redesign would have been difficult and expensive
– Electron spectrometer had no instrument purge port and would still need 
drag-on line
• Purge panels required updates in order to be used for DSCOVR
– Pressure relief valves now needed
– Filter models obsolete, new versions were smaller
– Switched to newer set of purge panels rather than update old panels
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Y Bakeouts and Thermal Vacuum Test
• Diffusion caused outgassing rates to rise to pre-bakeout levels
– Solar array took 3 days to return to pre-storage outgassing rates
– Known phenomenon that was seen consistently throughout program
– Needed to build that time into test estimates
• During storage preparations, some internal thermocouple wires were 
snipped too short, removing labels and complicating test 
preparations and data collection. 
8
Calrods
• Used three-step process to 
prepare new calrods for 
first use with DSCOVR
• Placed in highbay and 
run hot to burn off worst 
volatile species
• Placed in chamber and 
run hot with hot walls, no 
QCM
• Run in chamber with 
QCM to certify outgassing 
rate
• Should certify calrods at 100% power to 
allow for contingency during test.
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Y Environments and Bagging
• By end of program bagging had 
become a long process
– Needed to cutout, then individually bag 
star tracker, solar array harnesses, mag 
boom to distribute weight evenly
– Needed to triple bag for move to/from 
mag test site and for moves around ASO 
since observatory was being moved via 
forklift
– Needed a cart with nitrogen bottle and 
purge panel to keep purge active during 
forklift moves
– Extra bagging required close eye on 
internal bag temperature and dew points
– Placed temperature and RH monitors in 
bags to track changes
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• Know your environmental limitations and emergency access 
procedures 
• Lost power in B7/10/15 complex for 2 days after 2012 derecho storm
– Temperature went to 80°F, humidity to 70%
– Purge remained operational
– No evidence of condensation seen
– Limited emergency access stickers to project personnel at the 
time
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Y First NASA Mission on Falcon 9 
• DSCOVR launched on a Space X 
Falcon 9
• Instituted magnetic, particulate 
and molecular cleanliness 
requirements.
• Fairing was cleaned to an 
acceptable level 
• “Diving boards” used to access 
observatory for closeouts
• Purge gas certified to Grade B. 
Purge operated well throughout 
Falcon 9 operations. Disconnected 
~16hours prior to launch during final 
closeouts.
• Magnetic controls successful: flight 
magnetometer sees very little 
background noise.
• Contamination controls successful: 
camera and radiometer are 
operating well.
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DSCOVR Contamination Lessons Learned

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