ISO 23312:2022

Space systems — Detailed space debris mitigation requirements for spacecraft

This document defines detailed space debris mitigation requirements and recommendations for the design and operation of unmanned spacecraft in Earth orbit. This document defines detailed requirements that are applicable to: a) avoiding the intentional release of space debris into Earth orbit during normal operations; b) avoiding break-ups in Earth orbit; c) disposal of a spacecraft after the end of mission; d) estimating the mass of the remaining usable propellant; e) developing and maintaining the space debris mitigation plan. NOTE This document does not cover nuclear power sources on spacecraft.

Systèmes spatiaux — exigences détaillées pour la diminution des debris spatiaux relatifs aux satellites

General Information

• Status: Published
• Publication Date: 13-Jul-2022
• ICS: 49.140 - Space systems and operations
• Technical Committee: ISO/TC 20/SC 14 - Space systems and operations
• Drafting Committee: ISO/TC 20/SC 14/WG 7 - Orbital Debris Working Group
• Current Stage: 6060 - International Standard published
• Start Date: 14-Jul-2022
• Due Date: 20-Dec-2021
• Completion Date: 14-Jul-2022

Relations

• Revises: ISO 26872:2019 - Space systems — Disposal of satellites operating at geosynchronous altitude
• Effective Date: 10-Jul-2021
• Revises: ISO 16127:2014 - Space systems — Prevention of break-up of unmanned spacecraft
• Effective Date: 17-Jul-2021
• Revises: ISO 23339:2010 - Space systems — Unmanned spacecraft — Estimating the mass of remaining usable propellant
• Effective Date: 10-Jul-2021
• Revises: ISO 16164:2015 - Space systems — Disposal of satellites operating in or crossing Low Earth Orbit
• Effective Date: 17-Jul-2021

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 23312
First edition
2022-07
Space systems — Detailed space
debris mitigation requirements for
spacecraft
Systèmes spatiaux — exigences détaillées pour la diminution des
debris spatiaux relatifs aux satellites
Reference number
ISO 23312:2022(E)
© ISO 2022

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ISO 23312:2022(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2022
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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Published in Switzerland
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ISO 23312:2022(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols and abbreviated terms.2
5 Avoiding release of space debris into Earth orbit during normal operations .2
6 Avoiding break-ups in Earth orbit . 3
6.1 General . 3
6.2 Accidental break-up caused by an on-board source of energy . 3
6.2.1 General measures . 3
6.2.2 Subsystem-specific measures. 4
6.3 Accidental break-up caused by a collision . 5
6.3.1 Collision avoidance . 5
6.3.2 Assessment of the probability of structural break-up caused by impacts
with debris or meteoroid . 6
7 Disposal of spacecraft after the end of mission . 6
7.1 General . 6
7.2 Ensuring execution of disposal action . 6
7.3 Disposal to minimize interference with the GEO protected region . 7
7.3.1 General . 7
7.3.2 Developing basic manoeuvre requirements for a stable disposal orbit . 7
7.3.3 Developing long-term (100-year) disposal orbit characteristics . 7
7.3.4 Determining the manoeuvre sequence . 8
7.4 Disposal to minimize interference with the LEO protected region . 8
7.4.1 General . 8
7.4.2 Re-entry . 8
8 Estimating mass of remaining usable propellant . 9
8.1 General . 9
8.2 Uncertainty of estimation. 9
8.3 Incorporating required function into spacecraft design . 9
8.4 Documentation of data . 10
9 Space debris mitigation plan .10
9.1 General . 10
9.2 Break-up prevention plan . 11
9.3 End of mission disposal plan (EOMDP) . 11
9.4 Contingency plan .12
Annex A (informative) Procedure for estimating probability of accidental break-up .13
Annex B (informative) Examples of estimation methods .16
Annex C (informative) Deployable drag enhancement device .19
Bibliography .20
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ISO 23312:2022(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/
iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 20, Aircraft and space vehicles,
Subcommittee SC 14, Space systems and operations.
This first edition cancels and replaces ISO 16127:2014, ISO 16164:2015, ISO 23339:2010 and
ISO 26872:2019.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
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ISO 23312:2022(E)
Introduction
This document is developed to incorporate the content of ISO 16127, ISO 16164, ISO 23339, ISO 26872
and other detailed requirements relevant to spacecraft related debris mitigation, corresponding to
ISO 24113. The purpose of this document is to enable conformance with those high-level space debris
mitigation requirements in ISO 24113 that are relevant to spacecraft.
This document acts as one of the supporting technical standards for space debris mitigation, to provide
implementation requirements and details for the top-level requirements in ISO 24113.
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INTERNATIONAL STANDARD ISO 23312:2022(E)
Space systems — Detailed space debris mitigation
requirements for spacecraft
1 Scope
This document defines detailed space debris mitigation requirements and recommendations for the
design and operation of unmanned spacecraft in Earth orbit.
This document defines detailed requirements that are applicable to:
a) avoiding the intentional release of space debris into Earth orbit during normal operations;
b) avoiding break-ups in Earth orbit;
c) disposal of a spacecraft after the end of mission;
d) estimating the mass of the remaining usable propellant;
e) developing and maintaining the space debris mitigation plan.
NOTE This document does not cover nuclear power sources on spacecraft.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 24113:2019, Space systems — Space debris mitigation requirements
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 24113 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
acquiring organization
organization that plans and manages the development and acquisition contracts for the space system
Note 1 to entry: The responsibilities of the acquiring organization include the engineering and technical aspects
of the space system’s design and operations.
3.2
book-keeping method
method for determining fluid consumption by monitoring flow rates and the duration of propellant
expenditure periods
3.3
disposal orbit
orbit in which a spacecraft resides following the completion of its disposal actions
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3.4
PVT method
method for determining the remaining fluid quantity by estimating the mass of gas by deriving density
in a known volume from pressure and temperature measurements
3.5
remaining usable propellant
propellant that remains in the propellant system and that is effective for attitude and orbit control
manoeuvres excluding residuals and uncertainty
4 Symbols and abbreviated terms
ΔV delta velocity or total velocity change
EOL end of life
EOMDP end of mission disposal plan
GEO geostationary Earth orbit
LEO low Earth orbit
ṁ mass flow rate
MLI multilayer insulation
PVT pressure, volume, temperature
SDMP space debris mitigation plan
t time
5 Avoiding release of space debris into Earth orbit during normal operations
ISO 24113 specifies that a spacecraft shall be designed so as not to release space debris into Earth orbit
during normal operations. To satisfy this requirement, as a minimum, the following measures shall be
implemented.
a) Any appendage related to spacecraft normal operations shall be designed not to be released.
NOTE 1 Appendages include items such as apogee kick propulsion devices, fasteners of holding and
deployment mechanisms, caps, hoods, heat insulation enclosures, springs, explosive bolts and related
fragments.
b) Releasing parts essential for mission objectives should be assured not to pose a risk to the safety of
operating spacecraft and deteriorate the space environment.
c) Paint, MLI and surface materials that are exposed to the space environment, should be selected and
processes applied properly, to avoid flaking off from the spacecraft.
NOTE 2 Following ISO documents could help to assure compliance:
1) ISO 16691, Thermal control coatings for spacecraft — General requirements.
2) ISO 23129, Space systems — Thermal control coatings for spacecraft — Atomic oxygen protective
coating on polyimide film.
3) ISO 23230, Space systems — Paint materials — Processes, procedures, requirements.
d) Programs using tethers shall take extra measures to limit the collision risk with resident space
objects, and not to be severed with a single impact of debris or meteoroid.
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NOTE 3 Potential measure for tethered system is to apply multi-strand tether, to retract the tether in the
disposal phase.
6 Avoiding break-ups in Earth orbit
6.1 General
ISO 24113 specifies requirements to avoid the accidental break-up of a spacecraft in Earth orbit both
before and after its end of life. 6.2 and 6.3 provide detailed measures to help satisfy these requirements.
6.2 Accidental break-up caused by an on-board source of energy
6.2.1 General measures
6.2.1.1 Spacecraft design
The spacecraft design measures to prevent accidental break-ups caused by on-board source of energy
are as follows.
a) The calculations to determine the probability of accidental break-up while in orbit until its end of
life shall be performed and assessed with probability levels defined in ISO 24113:2019, 6.2.2.1.
NOTE 1 Annex A provides an example of an acceptable detailed evaluation approach.
b) Measures shall be designed to ensure that all on-board sources of stored energy can be depleted or
made safe and permanently deactivated once they are no longer required for the mission operation.
NOTE 2 Source can be residual propellants, batteries, high-pressure vessels, self-destructive devices,
flywheels, and momentum wheels.
c) The design of the on-board sources of stored energy shall take into account the following influences:
— the environmental extremes expected to be encountered during the normal operations;
— mechanical degradation during the normal operations;
— chemical decomposition;
— the effect of potential failure modes of the spacecraft during the mission, and
— what effect they would have on the ability to passivate the spacecraft.
d) The robustness of the design shall be confirmed during the design review process, to ensure that
adequate reliability and quality control has been performed to inhibit any failure that can lead to a
break-up event with a probability worse than specified in ISO 24113.
e) The first issue of passivation procedures shall be established prior to the end of the design phase.
6.2.1.2 Spacecraft operations
The spacecraft in-orbit operation measures to prevent accidental break-ups caused by on-board source
of energy are as follows.
a) For the operations of the spacecraft, procedures shall be defined to allow monitoring of the relevant
parameters of each subsystem, which has been identified as a potential source of space debris
generation, in order to detect malfunctions.
b) The following items, as a minimum, shall be monitored from the ground, if applicable:
— pressure and temperature in the engines, tanks, pressure vessels;
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— parameters (temperature and voltage) of batteries to detect failures;
— parameters to detect failure modes of the orbit and attitude control system.
c) Prior to the disposal phase, the passivation procedures shall be updated to take into account any
failures that have occurred during the mission and that affect the ability to passivate the spacecraft.
d) At the time when spacecraft operation is concluded either purposefully or due to malfunction and
disposal manoeuvres have been finished, passivation shall be performed.
NOTE If a controlled re-entry is to be performed, then passivation is not necessary.
e) In the event of in-orbit malfunctions which can lead to break-up or the loss of operating function,
a contingency plan to prevent debris generation should have been studied and, where appropriate,
implemented.
6.2.2 Subsystem-specific measures
6.2.2.1 Electrical systems
The specific measures for electrical systems are as follows.
a) The performance of batteries shall be monitored and assessed in accordance with standardized
procedures to assure the safety of the mission and post-mission disposal.
NOTE 1 Standardized procedure for health assessment of lithium-ion batteries can be found in
ISO/TR 20891.
b) Batteries and/or electrical systems shall be designed and manufactured, both structurally and
electrically, to prevent break-ups during all orbital life.
c) Pressure increase in battery cells and assemblies, potentially leading to a break-up, shall be
prevented.
NOTE 2 This can be done by mechanical measures for some types of batteries as far as it doesn’t decrease
the reliability.
d) At the end of operations, take measures to prevent re-charging to batteries, and discharge the
stored electric energy with assuring to keep necessary electric energy for following disposal action.
6.2.2.2 Propulsion systems
The specific measures for propulsion systems are as follows.
a) Pressure vessels, such as tanks and high-pressure gas bottles, shall be designed to avoid accidental
break-up caused by stored energy sources.
NOTE 1 ISO 14623 and ISO 24638 contain requirements relating to the design of pressure vessels.
b) For a bipropellant propulsion system, especially with hypergolic propellants, tanks and lines should
be designed so that any single-point failure does not cause the unplanned mixture or combustion of
the propellants.
c) Before end of life, as part of the disposal phase, the spacecraft shall have consumed or vented
residual liquid propellants and pressurized fluids, such as cold gas, liquefied gas, and propellant for
the fluid-based electric propulsion systems, which are potential sources of break-ups. Any residual
liquid propellants and pressurized fluids can be a source of break-ups also for spacecraft drifting
outside protected regions after end of life and should be consumed or vented to the maximum
extent as possible before end of life.
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d) End of venting shall be monitored (or confirmed), if appropriate, by proper means, such as on-
board pressure sensors, fluid gauging systems, thermal sensing, attitude sensing, or any other
demonstrable means.
e) If it is not possible to vent, a sufficient safety margin to ensure no break-ups under expected post-
disposal environmental conditions shall be adopted.
f) The venting system and process shall be designed not to be prevented by the frozen propellants.
g) The venting process should be defined to take into account any potential effects on the spacecraft’s
attitude or orbit and any ground visibility issues.
h) Solid rocket motors shall only be actuated in the case that there have been no sensor indications of
motor degradation due to mission-induced damage or due to adverse environmental conditions.
i) Solid motor should not be allowed if it generates slags in the GEO and LEO protected regions.
6.2.2.3 Pressurized systems such as heat pipes/fluid loops
All pressurized systems which are typically not designed to be vented, such as heat pipes/fluid loops,
shall be designed and qualified with safety margins that prevent break-up of the spacecraft when
considering thermal effects in orbit.
NOTE Specific venting operations for this kind of pressurized systems are not required in the disposal
phase.
6.2.2.4 Rotating hardware
The specific measures for rotating hardware are as follows.
a) All rotating devices, for example flywheels, reaction wheels, and momentum wheels, shall be
designed so that failure of the rotating part does not cause the break-up of the spacecraft under
nominal mechanical environmental conditions.
b) All rotating parts shall be allowed to de-spin, or stopped by termination of the power supply, at the
end of life.
6.2.2.5 Other devices
The specific measures for other devices are as follows.
a) Any other energy sources, such as pyrotechnically operated devices, shall be designed so that they
do not cause unacceptable risk of break-up and generate fragments.
b) Where this is unavoidable, the fragments shall be self-contained within the device which is affected
by break-up.
6.3 Accidental break-up caused by a collision
6.3.1 Collision avoidance
The spacecraft shall be designed and operated properly to prevent collision with trackable orbital
objects before its end of life.
a) During the mission operation, the conjunction assessment shall be conducted periodically against
potentially approaching objects based on the reliable orbit data.
b) Exchange of orbital parameters should be encouraged among spacecraft operators or space
agencies, to precisely check the close approach distance, and then determine an optimal avoidance
manoeuvre strategy for operators.
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c) The probability of collision with approaching trackable orbital objects shall be assessed during
operation.
NOTE 2 ISO/TR 16158 can be used to estimate the probability of collision.
d) If the risk of collision is above the threshold set by an approving agent, then the collision avoidance
manoeuvre (and/or returning manoeuvre) shall be planned and conducted appropriately, to reduce
the collision risk below the corresponding risk threshold.
6.3.2 Assessment of the probability of structural break-up caused by impacts with debris or
meteoroid
It is required to assess the probability of structural break-ups of spacecraft caused by impacts with
debris or meteoroid before its end of life.
a) The vulnerability of spacecraft against impact of space debris or meteoroid shall be assessed
during the design phase.
b) If the risk of structural break-up caused by impacts with debris is above the threshold set by an
approving agent, then the special design measures should be considered to minimize this risk.
NOTE 1 ISO 11227 and ISO 16126 provide guidance for analysing the impact risk from small debris impacts
and improving the design of spacecraft.
NOTE 2 The probability of successful collision avoidance, induced from the experience and authorized by
approving agent, can be incorporated into this assessment.
NOTE 3 The estimated probability of collision with trackable object will provide information of the expected
number of collision avoidance during operation and contribute on the planning of propellant allocation for 7.2 c).
7 Disposal of spacecraft after the end of mission
7.1 General
ISO 24113 specifies requirements for the disposal of a spacecraft after the end of mission so as to
minimize interference with the protected regions. 7.2 to 7.4 provide detailed measures to help satisfy
these requirements.
NOTE Measures to prevent break-up, as a part of disposal action, is written in 6.2.
7.2 Ensuring execution of disposal action
The measures to ensure execution of disposal action are as follows.
a) The probability of successful disposal should be determined during the design phase, and decide
to terminate the operation taking into account the events that have occurred during the operating
phase.
NOTE 1 In the case of highly eccentric orbits, considering the uncertainty in estimation of orbital
lifetime, the amount of propellant for disposal is designed to assure the compliance with 25-year rule with a
probability of more than 0,9. This is excluded from the probability of successful disposal of 0,9.
NOTE 2 Where possible, put in place well-organized systematic surveillance procedures, pre-planned
emergency actions, adequate procedures for determining the extension of the lifespan taking into account
deterioration or decommissioning, etc. The method to assess this probability can be determined by the
approving agent.
b) The availability of items concerning to the specific criteria shall be assured throughout the
designated (or planned) mission life.
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NOTE 3 Examples are estimated amounts of propellant remaining, redundancy remaining, status of
electrical power, status of systems critical to successful disposal, and time required to execute each disposal
action.
c) In order to reserve enough usable propellant to ensure the success of disposal manoeuvres, the
propellant used over the mission life shall be estimated with stated uncertainty; and the remaining
usable propellant shall be regularly monitored with quantified uncertainty.
NOTE 4 The remaining usable propellant can consider and include potentially needed collision avoidance
manoeuvres during operation.
NOTE 5 Clause 8 gives details for the estimation of remaining usable propellant.
d) A spacecraft should be injected into an intermediate (lower) altitude before transferring the
spacecraft to its final orbit for the planned operation, to provide the opportunity to check-out the
system, especially all critical systems required for controlling the spacecraft, performing collision
avoidance and post mission disposal.
e) The intermediate orbit should be designed preferably in a way that the spacecraft, even with critical
failures, naturally decays in accordance with the 25-year limit for the orbit lifetime as defined in
ISO 24113.
7.3 Disposal to minimize interference with the GEO protected region
7.3.1 General
ISO 24113 specifies that a spacecraft shall remain outside of, and not interfere with, the protected
regions for a period of at least 100 years after the end of its life.
a) Select a stable disposal orbit and conduct relating disposal manoeuvres for spacecraft before end
of life according to ISO 24113:2019, 6.3.2.2 or 6.3.2.3.
b) In the case of inclined GEO spacecraft, re-entry option is possible with feasible velocity increase
depending on the specific initial combination of inclination, eccentricity and ascending node. If
the orbital lifetime and dwell time passing through the protected orbital regions are acceptable
considering the contents of ISO 24113, it can be taken as a disposal option.
7.3.2 Developing basic manoeuvre requirements for a stable disposal orbit
A stable disposal orbit shall be established by one of the two options described below.
a) Use the eccentricity constraint as specified in ISO 24113:2019, 6.3.2.2 a) and Formula (1) to
determi
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