The topics are presented in viewgraph form and include the following: atomic oxygen attack; arcing and discharges; micrometeoroids and debris; state-of-the-art computer tools; current collection and snapover; effluents--neutral and ionized; and winds, dust, and contamination

Ferguson, Dale C.

English

NASA Technical Reports Server

N93-26898
SPACE ENVIRONMENTAL INTERACTIONS FOR THE SPACE EXPLORATION INITIATIVE
Dale C. Ferguson
National Aeronautics and Space Administration
Lewis Research Center
Cleveland, Ohio 44135
SPACECRAFT ENVIRONMENTAL EFFECTS
f u
Effluents _,I
,.,o,o,.o,.o,o,.._:===-'-',e ® '_¢
_(_ (_) PLASMA
Sputtering (_)
Space Environmental Interactions
Atomic Oxygen Attack
• LOW PLANETARY ORBITS ONLY
- Material Specific
- Preferentially in Ram
- Low MarsO, rblt Also Contains AO
- For Some=Ma.teria!s,'Synergy W/ UV
- Ionized AO Also Reactive.
• CHANGES MATERIAL SURFACE PROPERTIES
- Optical and Th,ermal Properties
Surface Conductivities
Strength of Exposed Fibers
69
https://ntrs.nasa.gov/search.jsp?R=19930017207 2020-03-17T05:41:57+00:00Z
1000 --
E
E
f_
100
I0
1.0
.1
.01
I(APTON HASS LOSS RATES VS, OXYGEN ENERGY
a - LeRC HIGI{ ENERGY ION BEAH I/J
b - RF PLASHA ASII_R " " _/
c - A_ROSPACK CORP. ATOMIC BEAH
d - LeRC STS-B'FLIGI|T RESULTS J'Jl_/
. - L.RC .1^sEo _r PLAs.A j//'e
-
.! 1..0. 10 I00 1000
E, eV
Copyright o AIAA 1986 - Used with permission. Visentine, J.T. and Leger,
L.J., A Consideration of Atomic Oxygen Interaction with the Space
Station, J. Spacecraft and Rockets, 23, 5, 505-511, 1986.
7O
ORIGINAL PAQE iS
OF POOR QUALITY
Load Biased to 100V Neg. w.r.t. Body
Z1.88
19.8e
17.elB
15._
Y 13.88
i !1.88
9.88
7.88
S.SqB
3.l_
1.88
-1._
-3._
3 S 7 9 11 13 IS 17 19 ZI Z3 ZS Z7 Z_; 31
Z-AXIS
Minimum Potential = -1.01E+eZ Haxi_JmPotential =-Z.72_-e8
3.88 (Z( 31.88, --3._ 1 (Y< Zlo_,' CUTPL_FF_E'TX =
Space Environmental Interactions
Arcing and Discharges
• GEOSYNCHRONOUS ENVIRONMENT
- Differential Charging in Geo Substorms
- Solar Flares in Interplanetary Space
• LOW PLANETARY ORBITAL ENVIRONMENTS
- Arcing TO or Thru Ionized Plasma
- Dielectric Breakdown of Anodized Surfaces
- Arcing at Conductor-Insulator Junctions
• PASCHEN BREAKDOWN- PLANETARY SURFACE
- Martian Atm Pressure Ideal for Discharges
- Lunar Camps Create Local Atmospheres
71
i0o
I0-I
10-2
i0-3
vm
e_
I0-4
I
J_
0 PIX IIflight
" • PIX II ground
I • Leung
• Miller
I0-5
I0-6
100
I
Threshold
I
2O0 600 I000 20O0
-V,V
Figure 7. - Arc rate versus voltagefor
$1andard interconnect cells. Normal-
ized to LEO ram conditions (see'lextl.
r
Copyright • AIAA 1986 - Used with permission. Ferguson, D.C., The
voltage threshold for arcing for solar cells in LEO-flight and ground test
results, AIAA paper 86-03621 1986.
72
Space Environmental Interactions
Micrometeoroids and Debris
• SURFACE DAMAGE
- Pinholes in Insulators
- Change of Thermal Properties
- Sites for Arcing, Sputtering
- Possible Site of Kapton Pyrolysis
• NEED FOR REDUNDANCY OR HEALING
- Fluid Lines and Heat Pipes
• LOCAL PLASMA CREATED AT SITE
- May Produce Prompt Arcing
- Arcs Enlarge Damaged Area
• DEBRIS PROBLEM IN PLANETARY ORBITS
10000 "1
I
4
.4
COUNTS
0.0
t.
J
C3 INSIDE CRATER
STS 7 WINDOW CRATER
'1''
ENERGY (KEV)
L|
10.0
73
Space Environmental Interactions
State-of-the-Art ,Computer Tools
• S-CUBED DIV. OF MAXWELL LABORATORIES
• NASCAP (3-D, Particle Tracking)
- Calculates Charging in GEO
- Obtainable thru COSMIC
- Mature Code, Industry Standard
• NASCAP/LEO (3-D, Particle Tracking)
- Calculates Charging, Currents in LEO
- Release thru COSMIC This Year
- Under Final Testing
• EPSAT, EWB (l-D, Systems Tools)
- Evaluate Multipl e Interactions
- QUick, APproximate
- Under Beta Testing
- May Be Ideal Starting Point for SEI
NASCAP model of NASA's
Advanced Communications Technology Satellite.
74
Figure 6
SP-IO0 Floating Potential
......, _._._,__:_EPSAT s Architecture Combines _::_,_,: ....
. /i .i A POwerfu!Dispiay_With •
/ Chan_beable & Expandable Modeling Capabilities
i!i i_ili_ii_!_ _ _i i¸ iiiiiiiiiii_i_!_i_iiiiiiiiiiiiiiiii!iiiiii!_i_i;ii iii ii i iii!i!iii!!iiiiiiiii!!iii __iiiiiiiiiiiiiiiiiiiili iii
iiii!iiiiiiiii_ i!!_ iiiiil//i/iiiiii • ............................
_':]__i0 _._:,_ _ I leuncllon=ll
_iiiiiiiiiiiiiiiiiii!iiiiii!iiiiiiiiiiiiiii!i!i!iii!iiiii!iiir_ _1 I moduleI .... ,
iliiii!iii!i!iN_N _ ', i_!ill i! i! ii{iiiiiiiiiiii i i!iiiil!ii iiiiiii!
_i_i_i_i_i_i_i_i_i_i_i_i_i_!_i_i_!_i_!_!_i_i_i_i_!_i_i_i_i_i_;'z z _ ............-- ................ !iiili!_i__ i i !!!i;ii
75
PO
_' _: wer System Models
I Column DensitiesSensor Degradation
Outgasslng J
Ambient
Environments
Plume - Ram
- Outgassing
Scattering
Plume IShields
Plumes
"10
o
LLJ
10 5
I 0 4
tO 3
10 2
10 _
I 0 °
i0-I
I0-2
i0-3
0 2 10 3
Orbit AIt;tude
Legend
o_
o _e
Total atomic oxygen erosion during a 10-year mission life for three
conductive coatings as a function of altitude for 60 ° inclination
circular orbits.
76
KAPTON41 HOURSEXPOSURETOATOMICOXYGENONSTS-8
15TS-8 FLXGHT SAMPLES
LeR¢ PRELIHIIt_RY riASS LOSS I_AS_I_IIT$
?67
77
ORIGINAL PAQ,E IS
OF POOR QUALITY
Space Environmental Interactions
Current Collection and Snapover
• ELECTRON COLLECTION AND SNAPOVER
- SnapOver at Potentials _ +100 V
- Insulators Act as Electron Conductors
- Large Power Drains
• ION,COLLECTION AND SPUTTERING
- Ions Focused Onto Insulation Defects
- Sputtering at Potentials _ -100 V
• FLOATING POTENTIALS
- ion and Electron Currents Must Balance
- Ease ofElectron Collection Makes
Systems Float Negative
• POWER SYSTEM GROUND IMPORTANT
- Grounds on Moon, Mars Difficult?
78
ARCING ON SOLARCELLARRAY SAMPLES
2x4 cm WRAPAROUNDCELLSON KAPTON
-1 kV BIASED ARRAY CIRCUIT
10.5cm-3 N PLASMA (2.5eV IONS, 3 eV e-)
NASA/LEWIS RESEARCHCENTER
ENVIRONMENTALINTERACTIONSPROGRAM
79
DIELECTRIC BREAKDOWN OF ANODIZED SURFACES IN A PLASMA
SSF Solar Array Negative Orounding Effects
Arc Rote on JgC Chromt¢ Acld Anodized Plote--0.'16 mTlAnodlzetlon
10
8
"15
.=.
_4
e,
IJ
J¢
2
.0
70
J
,t11_ .
J
,.I
.j
/.
/_
/
_o gO 100 110 120 130 140 150 160 170 1B0
BIo= Voltoga Relotive to Flootlng Potent]el IV]
8O
i
1.0E+04
1.0E+03
Peak Currents of Plasma Arcs
Beat Fit Powen 0,62+/-0.03
<
1.0E+02
+1
1.0E+01
1.0E÷()I
1.0E-O' •
1.0E-02 i
0.0001 0.001
......... • Snyder (Array)
: Bolmoln
I
0.01
81
Space Environmental Interactions
Effluents, Neutral and Ionized
• NEUTRAL EFFLUENTS
- Thruster Firings and Gas Dumps
- Change Vehicle Floating Potential
- May Interact Chemi_cak!!y .wit h__Surfaces
- May Become Ionized by UV, Critical
Ionization Velocity, Charge Exchange
- Source of Contamination
• IONIZED EFFLUENTS
- Ion Thrusters, Radioactive Sources
- May Be Attracted Back by E Fields
- Change Vehicle POtential .........
- Increase Local Plasma Density,
Arcing, sputtering, etc.
82
Space EnVironmental Interactions
Winds, Dust,. and Contamination
• NEUTRAL DUST CONTAMINATION
- P-rope||ed by Wir/d-s-0r Rocket Exhausts
- May Have High Sticking Factors
- Can Change Thermal, Optical Properties
- Attracted to Charged Surfaces by
Dipole Attractions
• CHARGED DUST
- Mars, Moon - Photoelectric Effect
- Mars - Triboelectric Charging
- Attracted Strongly to Charged Surfaces
83
B4
85



Space environmental interactions for the space exploration initiative

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