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Suggested Citation:"INDEX." National Research Council. 1995. Orbital Debris: A Technical Assessment. Washington, DC: The National Academies Press. doi: 10.17226/4765.
×

Index

A

Altitude

collision velocities and, 88, 89

debris population growth trends, 157

distribution of debris populations by, 64-68, 76

duration of orbital lifetime and, 1, 28, 30

likelihood of collision with debris and, 4, 81-82, 85-86, 98

medium-sized debris distribution, 71-74, 76

meteoroid flux and, 84

object velocity variation, 93

small debris distribution, 74, 76

tracking ability and, 34-35

See also Orbital regions

Aluminum oxide particles, 11, 24, 75, 76, 111

Analytic/numerical impact modeling, 5, 102, 109-110, 112, 114-115, 121-122

Angle of impact, 88, 90-91, 121

Arecibo Observatory, 40, 41

Ariane launch vehicle, 137, 141, 142

Astronomical observation, 13

Atmospheric drag, 1, 20, 27-28, 36, 55-56, 70, 71, 75, 145-146

B

Ballistic limit, 109, 111, 197

Batteries, 139

Breakup(s)

collision with debris as cause of, 4, 12, 91-92, 98, 138

debris population growth and, 168-172

defined, 197

explosion model, 138-139

in GEO, distribution of debris, 149

hypervelocity test simulations, 102, 112-114

modeling, 4, 54-55, 70, 91-92, 98, 160, 168-172

numbers of, 25

radioactive materials in, 91

recommendations for prevention of, 8, 181

reducing debris from, 139-142

rocket body, 140-141, 154

as source of fragmentation debris, 25, 70, 75

test collisions, 91-92

Brem-Sat spacecraft, 47

BUMPER probability analysis code, 121

C

Cassini spacecraft, 47

Cataloging.

See Tracking and cataloging

CHAIN modeling program, 53, 163

Charge-coupled devices, 2, 37

Clementine 1 interstage adaptor, 48

Clouds of debris, 25, 55, 75-76

COBE.

See Cosmic Background Explorer

Suggested Citation:"INDEX." National Research Council. 1995. Orbital Debris: A Technical Assessment. Washington, DC: The National Academies Press. doi: 10.17226/4765.
×

Collision avoidance/warning systems, 6, 36, 43

applications to date, 125, 127

development prospects, 127-128, 131-132, 143

ground-based sensors for, 126-127

shoot-back schemes, 128

in Space Shuttle operations, 127

spacecraft-based sensors for, 125-126

spacecraft maneuverability for, 126

Collision effects

accuracy of models, 160

analytical/numerical modeling, 5, 102, 109-110, 114-115

angle of impact and, 88, 90-91

breakups as, 4, 12, 91-92, 98, 138

collisional growth of debris population, 6-7, 102, 143, 158, 160-167, 172

damage scaling laws, 46

experiences to date, 12, 13

hazards to crewed missions, 95

impact conditions in determination of, 4, 88-91

impact damage scaling laws, 46

limitations in damage assessment capabilities, 46, 79, 111-114

performance deterioriation models, 97, 109

range of, 4-5, 11-12

recommendations for research, 5-6, 179

research strategies, 5, 101

structural and component damage, 4-5, 93-95, 97, 98-99, 121-122

tether damage, 97, 99

velocity and, 4, 67

vulnerability of spacecraft surface, 95-98, 99

Coolant leakage, 74, 95

Cosmic Background Explorer (COBE), 25

Crewed missions

impact hazards to, 95

release of mission-related debris, 136, 137

D

Debris flux, definition of, 197

Debris swarms, 46, 47, 75-76

Delta rocket bodies, 140

Depletion burns, 141

Deterioration products, 25-27

Disposal orbits, 22

concerns about, 8, 152-153

location of, 148-149, 152, 153

recommendations, 9, 181-182

to reduce debris hazards, 8, 147-148, 152-153, 154

reorbiting costs, 150

Drag augmentation, 145-147

Duration of orbit.

See Orbital decay

E

Electromagnetic rail gun, 104, 106

European Retrievable Carrier, 13, 45, 46, 74

European Space Agency, 13, 52, 121, 176, 188

EVOLVE, 53, 81-82, 158

Explorer spacecraft, 47

Explosive bolts, 24, 136

F

Fragmentation debris, 198

in breakup modeling, 92, 98

current population estimates, 25

degradation products, 25-27, 75

distribution, 25, 64, 138

hypervelocity tests, 102-103

medium-sized, 70

small-sized, 75

sources of, 25

strategies for reducing, 138-142

G

GEO.

See Geosynchronous Earth orbit

Geostationary Earth orbit, 18, 199-200

Geostationary Operational Environmental Satellite, 23

Geostationary transfer orbits

definition, 199

ground-based optical sampling of, 39

risk of debris collision in, 87

solar-lunar perturbational forces in, 28

Geosynchronous Earth orbit (GEO), 1

collision effects in, 93

collision velocities in, 90

collisional growth of debris population in, 167

definition, 18, 200

disposal orbits for, 8, 9, 148-149, 152, 154, 182

Suggested Citation:"INDEX." National Research Council. 1995. Orbital Debris: A Technical Assessment. Washington, DC: The National Academies Press. doi: 10.17226/4765.
×

distribution of debris in, 2, 69, 84-87

ground-based optical sampling of, 39

large debris object distribution in, 63-64, 67-69

likelihood of collision with debris in, 4, 85-87, 98

modeling of breakup debris in, 149

orbital inclination of debris in, 68-69, 86

recommendations for characterization studies, 177

space-based sampling in, 44

spacecraft design for, 23, 24, 121

spacecraft distribution in, 19

stable plane, 152

stable points, 152

uses of, 18

Global Positioning System, 19, 148

Goldstone Deepspace Communications Complex, 40, 41

Gravitational forces, 27, 28, 69, 145

H

Haystack radar, 13, 40-41, 70-74, 81

Auxiliary Radar, 41-42

High Earth orbits, 18-19

definition, 199

density of debris in, 84-85

likelihood of collision with debris in, 84-87, 98

Hiten spacecraft, 47, 75

Hubble telescope, 42, 45

Hydrocode, 110, 198

Hypervelocity launcher, 104-106

Hypervelocity testing

access to test data and testing facilities, 5, 6, 108, 114, 179

with analytical/numerical modeling, 5, 102, 109-110, 114-115

capabilities and techniques, 5, 103-107

design of, 102-104

dissimilar materials testing, 106-107

of fragmentation effects in breakup, 102, 112-114

hypervelocity defined, 198

limitations, 111, 114

purpose, 101-102, 114, 121

recommendations, 5-6, 179

simulated impacts, 107

spacecraft component testing, 102, 130-131

velocity capabilities, 103, 104-105, 106

velocity requirements, 103

I

In situ debris sampling, 2

active measurements, 46-48

advantages, 45

basis of, 45

limitations, 45-46, 48, 57-58

opportunities for improvement, 48-49

passive measurements, 45-46

Inclination

angle of impact related to, 91

collision velocities and, 88-90

definition, 198

distribution of large debris objects, 67-69

GEO stable plane, 152

likelihood of collision with debris and, 4, 82-84, 86, 98

limits of radar detection, 40

of medium-sized orbital debris, 71-74

tracking and, 35

Infrared Astronomical Satellite, 42

Infrared debris detection systems, 43

Inter-Agency Space Debris Coordination Committee, 176, 187

International Astronautical Academy, 187-188

International efforts

debris reduction strategies, 8, 180

national policies and, 188

for orbital debris research, 3

for orbital debris tracking and cataloging, 3, 35, 177-178

recommendations, 3, 176, 177-178, 180

space laws, 180, 185-188

International Law Association, 187

International Space Station, 121, 125, 127

K

Kosmos spacecraft, 25

L

Launch vehicles, 17

Law, international, 180, 185-188

LEO.

See Low Earth orbit

Light gas guns, 104, 105, 107, 198

Long Duration Exposure Facility, 12, 14, 45, 46, 74, 142-143

debris impact prediction, 90-91

Suggested Citation:"INDEX." National Research Council. 1995. Orbital Debris: A Technical Assessment. Washington, DC: The National Academies Press. doi: 10.17226/4765.
×

debris swarms, detection by, 75-76

Interplanetary Dust Experiment, 47, 75

surface damage from debris impacts, 95, 97-98

surface degradation, 27

Low Earth orbit (LEO), 1

assessment of debris reduction proposals for, 168-169

characterizations of debris population in, 3, 34, 49-50, 57, 63, 80-81

collision effects in, 93

collision velocities in, 88-90

collisional growth of debris population in, 7, 164-167

definition, 199

determinants of orbital lifetime in, 28

disposal orbits in, 8, 181-182

ground-based optical sampling, 38-39

ground-based radar sampling, 39-41, 42

large debris object distribution in, 63-64, 67

likelihood of collision with debris in, 4, 81-84, 98

predictions for growth of debris in, 7, 172

propagation models, 56-57

rocket body debris in, 23

space-based sampling in, 44

spacecraft design for, 23

spacecraft distribution in, 18, 19

spread of fragmentation debris in, 138-139

tracking and cataloging of orbital debris in, 2-3, 36, 57, 177

uncataloged debris in, 81

Lunar effects on orbital lifetimes, 28, 56, 145

M

Materials models, 5, 110, 111, 179

Measurement of debris environment

completeness of current data set, 2, 49-50, 63

estimating atmospheric drag effects, 27-28, 36, 56

estimating methodologies, 31

modeling techniques for, 51-57

opportunities for improvement, 50-51, 177

See also Sampling;

Tracking and cataloging of orbital debris

Meteoroids, 1

collision risk in GEO relative to debris, 86

hazards to space operations from, 3, 11, 76, 84

Midcourse Space Experiment, 43

Mir space station, 12, 13, 24, 45, 74

Mission-related debris

definition, 198-199

distribution, 64-65, 136

intentional dumping of, 24

medium-sized, 70

recommendations, 8, 181

rocket exhaust as, 24-25, 75, 136, 137

small-sized, 74-75

sources of, 24

strategies for reducing release of, 136-137

Modeling, 3

analytical/numerical impact, 5, 102, 109-110, 114-115

breakup modeling, 54-55, 70, 160

collisional cascading, 161-167

debris cloud, 55

debris impact risk, 120-122

debris reduction strategies, 167-172

debris shapes, 111, 114

ESA Reference Model for Space Debris and Meteoroids, 121

future debris population, 52-53, 58, 157-167

materials research for impact, 5, 110, 111, 179

opportunities for improvement, 58

performance deterioration, 97, 109

population characterization, 51-52, 58

propagation models, 55-57

purpose, 51

recommendations for research, 5-6, 176, 177

standard population characterization reference model, 3, 52, 177

traffic modeling, 53-54

Molniya orbits, 28, 64, 67-68, 86

definition, 199

spacecraft distribution in, 19

N

NEXTEL shield, 125

Nonfunctional spacecraft, 21-22, 68

Suggested Citation:"INDEX." National Research Council. 1995. Orbital Debris: A Technical Assessment. Washington, DC: The National Academies Press. doi: 10.17226/4765.
×

O

Orbital Debris Radar Calibration Spheres, 41

Orbital decay

altitude and, 1, 28, 30

determinants of, 1, 27-28, 30

orbital lifetime reduction strategies, 144-147, 154, 199

projections of, 28

propagation models, 55-57

Orbital Meteoroid and Debris Counter, 48

Orbital regions, 1, 199-200

collision velocities, 88-90

distribution of spacecraft in, 18-20

hazard from debris and, 79, 80

location of disposal orbits, 8, 148-149, 152, 153

perturbation forces in, 27

probability of collision with debris in, 4

See also Altitude;

specific orbit

P

Paint chips, 11, 26-27, 75, 97-98, 142, 181

Palapa spacecraft, 45

Peer review, 3, 178

Pegasus spacecraft, 47

Perturbation forces, 27-30

effects on small debris, 75, 158

in GEO stable plane, 152

modeling of, 55-56, 159

size of debris objects and effects of, 70

use of, for lifetime reduction maneuvers, 145

Plasma drag launchers, 106

Political and economic contexts, 8, 180

Population characterization models, 51-52, 58

Progress M cargo spacecraft

Propagation models, 55-57

Protection against debris hazards

active systems, 122, 125-128, 131-132

benefit-cost analysis in spacecraft design, 119-120

experimental testing of systems for, 101

mission design for, 128-129

operational protection, 122, 128-129

passive strategies, 122-125

risk assessment for spacecraft design, 120-122

spacecraft design for, 6, 178-179

See also Collision warning/avoidance;

Shielding

Proton launch vehicle, 23

Q

Quantity of debris, 3, 11

current catalog, 20, 21, 25

current estimate, 63

debris collisions as source of growth in, 6-7, 102, 143, 158, 160-167, 172

fragmentation sources, 25, 138, 140

growth trends, 157, 158, 172

from intentional spacecraft breakups, 140

large debris population, 63-67

medium-sized debris population, 3, 70-74, 76

mission-related sources, 136

models for estimating, 157-167

number vs. mass, 143, 154, 167

predictions for growth in, 6-7, 52-53, 119

rocket body fragments, 140

small-sized debris population, 74, 158, 177

spacecraft explosion as a source, 139

strategies for reducing growth in, 7-8, 135-136

variation by orbital region, 84-85

R

Radar cross section, 34

Radar Ocean Reconnaissance satellites, 74

Radar observation, 3, 36

calibration techniques, 41

current activities, 36, 39-41

limits of, 34, 36

opportunities for improvement, 41-42, 57

RADARSAT spacecraft, 121, 130-131

Radioactive materials, 22, 91

Reducing debris hazards

by active in-orbit removal, 7, 143, 153-154, 180

assessment of strategies for, 135-136, 167-172

cost considerations, 136

data needs for, 175

deorbiting/lifetime reduction strategies for, 7-8, 143, 144-147, 154, 169, 171, 172

international efforts, 180

Suggested Citation:"INDEX." National Research Council. 1995. Orbital Debris: A Technical Assessment. Washington, DC: The National Academies Press. doi: 10.17226/4765.
×

long-term strategies, 135

mass vs. number of objects as goal of, 167

from mission-related debris, 136-137, 154

recommendations for, 8-9, 180-182

by reducing creation of debris from collisions, 143, 172

reorbiting to disposal orbits for, 147-153, 154, 181-182

from spacecraft degradation, 142-143, 181

spacecraft design strategies for, 7, 8, 129-132

from spacecraft explosions, 138-142, 154

spacecraft operations for, 7-8, 128-129, 135

See also Protection from debris hazards

Redundant design, 6, 128

Removal of debris, 7, 143, 153-154, 180

Research

analytical/numerical impact modeling, 5, 102, 109-110

damage assessment and prediction, limitations of, 111-114

data sources, 13-14

on effects of debris impacts, opportunities for, 101

measurement of debris environment, current status of, 49-51

peer review, 3, 178

recommendations for, 3, 5-6, 176-178

shielding, 125

See also Hypervelocity testing;

Modeling

Risk of collision

benefit-cost analysis of spacecraft design, 119-120

current estimates, 2, 9

determinants of, 79, 80, 98, 120

growth in, 11, 12-13, 119, 172

in HEO, 4, 84-87, 98

in LEO, 4, 80-84, 98

with meteoroids, 3, 11, 76, 84, 86

modeling, 120-122

with objects surviving reentry, 1, 13

orbital altitude and, 4, 81-82, 85-86, 98

orbital inclination and, 4, 82-84, 86, 98

predictions for LDEF, 90-91

radioactive materials and, 91

research needs, 2-3, 175-176

size of objects and, 3-4

spacecraft design considerations, 120-122

See also Reducing debris hazards

Rocket bodies, 200

contribution to debris population, 11, 23-24, 140

debris distribution, 65

passivation of, to reduce debris growth, 140-142, 181

Rocket exhaust, 11, 24-25, 75, 136, 137

Russian Space Agency, 176

S

Salyut space stations, 12, 45, 46-47, 74

Sampling

completeness of current data set, 49-50

with ground-based optical sensors, 38-39

with ground-based radar, 39-42, 70-71

opportunities for improvement, 58

from orbit, 42-44

purpose of, 2, 38

in situ, 2, 45-49

strategies for, 2, 38

Semisynchronous orbit, 1, 199

collision risk in, 98

debris distribution, 84

orbital velocity, 90

spacecraft distribution in, 19

Shape of debris, 111, 114

Shielding, 5, 11, 179

analytical/numerical modeling of, 109

current research efforts, 125

current technology, 6, 103

design considerations, 102, 123, 131

hypervelocity testing of, 102

obstacles to development, 111

size of debris objects and, 122

types of, 123

Whipple type, 123-125

Size of debris objects

breakup fragments, 54-55, 70, 75, 92

debris flux and, 80

distribution estimates, 63

effect of impact and, 12, 88, 93-95

large, 3, 4, 63-70

limits of ground-based optical sampling, 2, 38-39

limits of in situ sampling, 49

limits of radar detection, 35-36

limits of space-based remote sensing, 44

limits of space-based sampling, 42, 44

measurement conventions, 21

medium-sized, 3, 4, 48-49, 57-58, 70-74, 76

Suggested Citation:"INDEX." National Research Council. 1995. Orbital Debris: A Technical Assessment. Washington, DC: The National Academies Press. doi: 10.17226/4765.
×

perturbation forces and, 70, 71, 75

population growth trends, 161

probability of collision in LEO, 4

radar cross section, 34

rocket exhaust particles, 24

shielding considerations, 122

small, 4, 74-76, 158, 177

tracking ability, 2-3, 34, 35-36, 57

Skylab, 42, 45

Solar effects on orbital lifetimes, 27-28, 56, 145, 200

Solar Maximum Mission, 12, 45, 74

Space Shuttle, 12, 45, 74, 82

collision avoidance procedure, 127

mission design to reduce impact risk, 129

Space Station Freedom, 13, 121

Space suits, 95

Space Surveillance Network, 20, 32, 34, 35, 201

Space Surveillance System, 32, 34, 35, 36, 201

Spacecraft design, 5

analytical/numerical modeling in, 109

benefit-cost analysis, 119-120

debris removal vehicles/devices, 153-154

for deorbiting/lifetime reduction maneuvers, 144-145

drag augmentation devices, 145-147

early process, 120, 131

fuel demands for reorbiting to disposal orbit, 150

historical concerns with debris impacts, 119

hypervelocity testing, 101-103, 121-122

impact risk assessment, 120-122

oversizing, 128

passivation strategies to reduce debris population growth, 139-140, 181, 200

protection from debris impacts in, 7, 88, 90-91, 128, 130-131

recommendations, 6, 8, 178-179, 181

for reducing degradation debris, 142-143, 181

redundant components, 6, 128

rocket bodies, 23

shielding, 102, 122-125, 131

solar power systems, 98

strategies for reducing breakup debris, 138-142, 181

surface materials, 181

understanding of debris environment for, 175-176

vulnerability of components to debris impacts, 93-95, 99, 121-122

Spacecraft operations

breakup modeling, 54-55

collision avoidance systems, 125, 126

definition of functional spacecraft, 20-21

deorbiting/lifetime reduction maneuvers, 7-8, 143, 144-147

experimental simulation of debris impact effects, 101

historical development, 11, 17, 20

impact risk reduction, mission design in, 128-129

intentional breakups, 8, 25, 140, 181

orbital distribution, 18-20

orbital placement, 17-18

in reducing debris hazard, 7-8, 9

reducing release of mission-related debris in, 136-137, 154

sources of debris from, 21-27

surface damage from debris impacts and, 97-98

traffic modeling, 53-54

venting of residual propellant, 139-140, 141-142

Spallation, 93, 201

SPELDA device, 137

Sun-synchronous orbit, 18, 199

T

Telescopic observation, 2-3, 35

charge-coupled devices in, 2, 37

limitations of, 38

liquid-mirror, 39

with modeling techniques, 52

opportunities for improvement, 39

for sampling, 38-39

space-based, 42-43, 97

vulnerability of space-based optics to debris impacts, 97

Tethers, 97, 99

Titan rockets, 137

Toroidal cloud.

See Clouds of debris

Tracking and cataloging of debris objects

for collision warning/avoidance systems, 125, 126-127

current capabilities, 2, 14, 31-36, 57

Suggested Citation:"INDEX." National Research Council. 1995. Orbital Debris: A Technical Assessment. Washington, DC: The National Academies Press. doi: 10.17226/4765.
×

current catalog, 20, 21, 57, 63, 67, 70, 84-85

definition, 197

medium-sized debris population, 70-74

need for, 175-176

opportunities for improvement, 2-3, 35-37, 57

predictive ability, 36, 55, 57

recommendations for, 3, 177-178

uncataloged debris in LEO, 81

uncataloged large debris, 69-70

Traffic modeling, 53-54

Types of orbital debris, 1, 11, 20-27

coolant leakage, 74

debris swarms, 75-76

degradation products, 25-27

intentionally dumped, 24

oldest spacecraft debris, 22

radioactive, 91

See also specific types

U

United Nations, 185-187

Use of space, 1, 17

growth of debris population, 2

international law and treaties, 180, 185-188

predictive modeling, 53-54

trends, 18-19

See also Spacecraft operations

V

Velocity, 67

altitude variation and, 93

of breakup debris, 70, 92

collision, 11-12, 88-90

energy of high velocity objects, 93

in GEO stable plane, 152

in geostationary transfer orbits, 87

shield design considerations, 123-124

W

Westar spacecraft, 45

Whipple bumper shield, 111, 123-125

Suggested Citation:"INDEX." National Research Council. 1995. Orbital Debris: A Technical Assessment. Washington, DC: The National Academies Press. doi: 10.17226/4765.
×
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Suggested Citation:"INDEX." National Research Council. 1995. Orbital Debris: A Technical Assessment. Washington, DC: The National Academies Press. doi: 10.17226/4765.
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Suggested Citation:"INDEX." National Research Council. 1995. Orbital Debris: A Technical Assessment. Washington, DC: The National Academies Press. doi: 10.17226/4765.
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Suggested Citation:"INDEX." National Research Council. 1995. Orbital Debris: A Technical Assessment. Washington, DC: The National Academies Press. doi: 10.17226/4765.
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Suggested Citation:"INDEX." National Research Council. 1995. Orbital Debris: A Technical Assessment. Washington, DC: The National Academies Press. doi: 10.17226/4765.
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Suggested Citation:"INDEX." National Research Council. 1995. Orbital Debris: A Technical Assessment. Washington, DC: The National Academies Press. doi: 10.17226/4765.
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Suggested Citation:"INDEX." National Research Council. 1995. Orbital Debris: A Technical Assessment. Washington, DC: The National Academies Press. doi: 10.17226/4765.
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Suggested Citation:"INDEX." National Research Council. 1995. Orbital Debris: A Technical Assessment. Washington, DC: The National Academies Press. doi: 10.17226/4765.
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Orbital Debris: A Technical Assessment Get This Book
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Since the beginning of space flight, the collision hazard in Earth orbit has increased as the number of artificial objects orbiting the Earth has grown. Spacecraft performing communications, navigation, scientific, and other missions now share Earth orbit with spent rocket bodies, nonfunctional spacecraft, fragments from spacecraft breakups, and other debris created as a byproduct of space operations. Orbital Debris examines the methods we can use to characterize orbital debris, estimates the magnitude of the debris population, and assesses the hazard that this population poses to spacecraft. Potential methods to protect spacecraft are explored. The report also takes a close look at the projected future growth in the debris population and evaluates approaches to reducing that growth. Orbital Debris offers clear recommendations for targeted research on the debris population, for methods to improve the protection of spacecraft, on methods to reduce the creation of debris in the future, and much more.

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