ISO 24113:2019 スペースシステム—スペースデブリの軽減要件 | ページ 6

3.1

approving agent

entity from whom approval is sought for the implementation of space debris (3.23) mitigation requirements with respect to the procurement of a spacecraft (3.25) , or its launch, or its operations in outer space, or its safe re-entry (3.22) , or a combination of those activities

3.2

break-up

event that completely or partially destroys an object and generates space debris (3.23)

3.3

casualty risk

expected number of casualties

situation expressed by the probability that at least one person is killed or seriously injured as a consequence of an event

Note 1 to entry: The medical profession has defined a number of different injury scoring systems to distinguish the severity of an injury. Broadly, a serious injury is one of such severity that hospitalisation is required.

Note 2 to entry: The re-entry (3.22) of a spacecraft (3.25) is an example of an event.

3.4

controlled re-entry

type of re-entry (3.22) where the time of re-entry is sufficiently controlled so that the impact of any surviving debris on the surface of the Earth is confined to a designated area

Note 1 to entry: The designated area is usually an uninhabited region such as an ocean.

3.5

disposal

actions performed by a spacecraft (3.25) or launch vehicle orbital stage (3.13) to permanently reduce its chance of accidental break-up (3.2) and to achieve its required long-term clearance of the protected regions (3.21)

Note 1 to entry: Actions can include removing stored energy and performing post-mission orbital manoeuvres.

3.6

disposal manoeuvre

action of moving a spacecraft (3.25) or launch vehicle orbital stage (3.13) to a different orbit as part of its disposal (3.5)

3.7

disposal phase

interval during which a spacecraft (3.25) or launch vehicle orbital stage (3.13) performs its disposal (3.5)

3.8

Earth orbit

bounded or unbounded Keplerian orbit with Earth at a focal point, or Lagrange point orbit which includes Earth as one of the two main bodies

Note 1 to entry: For the purposes of this document, it is not necessary to consider space objects (3.24) in unbounded Keplerian orbits if their probability of interference with the LEO and GEO (3.11) protected regions (3.21) is negligible.

3.9

end of life

Note 1 to entry: See Annex A.

3.10

end of mission

Note 1 to entry: See Annex A.

3.11

geostationary Earth orbit

GEO

Earth orbit (3.8) having zero inclination, zero eccentricity, and an orbital period equal to the Earth's sidereal rotation period

3.12

launch vehicle

DEPRECATED: launcher

system designed to transport one or more payloads into outer space

3.13

launch vehicle orbital stage

complete element of a launch vehicle (3.12) that is designed to deliver a defined thrust during a dedicated phase of the launch vehicle’s operation and achieve orbit

Note 1 to entry: Non-propulsive elements of a launch vehicle, such as jettisonable tanks, multiple payload structures or dispensers, are considered to be part of a launch vehicle orbital stage while they are attached.

3.14

Launching State

State that launches or procures the launching of a spacecraft (3.25) , or State from whose territory or facility a spacecraft is launched

Note 1 to entry: This definition is consistent with the definition in the UN Liability Convention^[5] and the UN General Assembly’s Resolution 59/115 on the notion of the Launching State^[6].

3.15

mission

set of tasks or functions to be accomplished by a spacecraft (3.25) or launch vehicle orbital stage (3.13) , other than its disposal (3.5)

3.16

mission lifetime extension

postponement of the previously defined end of mission (3.10)

3.17

normal operations

execution of the planned tasks or functions for which a spacecraft (3.25) or launch vehicle orbital stage (3.13) was designed

Note 1 to entry: Normal operations include the disposal phase (3.7) .

3.18

orbit lifetime

elapsed time between an orbiting space object’s (3.24) initial or reference position and its re-entry (3.22)

Note 1 to entry: Examples of"initial position" are the injection into orbit of a spacecraft (3.25) or launch vehicle orbital stage (3.13) , or the instant when space debris (3.23) is generated. An example of a"reference position" is the orbit of a spacecraft or launch vehicle orbital stage at the end of mission (3.10) .

3.19

passivate

<space debris mitigation> act of permanently depleting, irreversibly deactivating, or making safe all on-board sources of stored energy capable of causing an accidental break-up (3.2)

Note 1 to entry: Passivation reduces the chance of an accidental explosion that could generate space debris (3.23) .

Note 2 to entry: Residual propellants, batteries, high-pressure vessels, self-destruct devices, flywheels and momentum wheels are examples of on-board sources of stored energy capable of causing an accidental break-up.

3.20

probability of successful disposal

probability that a spacecraft (3.25) or launch vehicle orbital stage (3.13) is able to complete all of the actions associated with its disposal (3.5)

Note 1 to entry: The calculation of this probability includes consideration of uncertainties in the availability of resources, such as propellant, required for the disposal.

Note 2 to entry: The calculation of this probability can include consideration of the inherent reliabilities of subsystems that are necessary to conduct the disposal, monitoring of those subsystems, and operational remediation of any observed subsystem degradation or failure.

Note 3 to entry: The calculation of this probability can include an assessment of the risk that a space debris (3.23) or meteoroid impact will prevent the disposal, but this is not mandatory.

Note 4 to entry: In the previous edition of this document, ISO 24113:2011, the probability of successful disposal was defined as a conditional probability, i.e. the probability of successfully performing a disposal given that the nominal mission (3.15) had been completed. In this document the probability is no longer conditional.

3.21

protected region

region in outer space that is protected with regard to the generation of space debris (3.23) to ensure its safe and sustainable use in the future

3.22

re-entry

permanent return of a space object (3.24) into the Earth’s atmosphere

Note 1 to entry: Several alternative definitions are available for the delineation of a boundary between the Earth’s atmosphere and outer space.

3.23

space debris

DEPRECATED: orbital debris

objects of human origin in Earth orbit (3.8) or re-entering the atmosphere, including fragments and elements thereof, that no longer serve a useful purpose

Note 1 to entry: Spacecraft (3.25) in reserve or standby modes awaiting possible reactivation are considered to serve a useful purpose.

3.24

space object

object of human origin which has reached outer space

3.25

spacecraft

system designed to perform a set of tasks or functions in outer space, excluding launch vehicle (3.12)