abbreviated terms

APIApplication programming Interface
CADComputer Aided Design
COLACOLlision Avoidance
GEOGeostationary Earth Orbit
LEOLow Earth Orbit
MEOMedium Earth Orbit
NORADNorth America Aerospace Defense
SSASpace Situational Awareness
SSRSpace Sustainability Rating


This section addresses the information satellite and launch vehicle operators should share with peers and stakeholders, as well as the contribution of such information-sharing to spaceflight safety. Potential forms of data sharing are divided into three categories:

  1. Collision Avoidance Coordination Information
  2. Satellite Metric Information
  3. Characterization Information

There are four potential sharing audiences, described in the list below. Operators may gain points by sharing a given type of information (listed in Table 2) with a particular audience. Information and data sharing in this module includes both publication and update commitments (i.e. operators must commit and follow through on keeping the relevant form of data up-to-date in addition to sharing it to receive credit). The specific updated cadence depends on form of data, but should be reasonable to support common operational uses of that information – unless thoroughly specified.

To achieve credit for sharing a specific type of data with a particular audience, the SSR applicant should generally make the data available to entities in that particular category on a reasonable and non-discriminatory basis. It is not required however to proactively demonstrate that every potential possible entity in a category has the capability to receive their data (e.g.  making data available in a commonly used data format is enough, even if a subset of potentially users have systems that do not support that format).

Category of audiences:

  • SSA Providers

Many entities operate SSA databases for use by third parties or provide SSA data products or services to others. Some of these entities are governmental, others are operated as non-profits or in academia, and some are for profit entities.  Sharing with such entities earns the SSR applicant this form of credit.

  • Other operators upon request for coordination

Another operator may issue a request for coordination to an SSR applicant in response to a high interest event, or other specific planned or emergent event.  Operators may be willing to share information with other entities with a credible need to know in response to such an event. Such sharing earns an SSR applicant credit for sharing in this category.

  • Voluntary network of operators/stakeholders

Various organizations, including the Space Data Association, exist as venues to share safety of flight information, with some providing additional data verification and validation and/or legal and technical restrictions on the use of shared information. Informal networks also exist for various spacecraft operators with overlapping orbits, where data sharing happens on ad-hoc bases and to serve specific needs of operators. Such information networks are put in place when a mission has strict requirements, e.g. in terms of ground track patterns, or potential interferences as part of orbital manoeuvre campaigns, e.g. tandem flights or crossing specific orbital regions, are identified. Sharing with such organizations would earn credit under this item.

  • General public

In order to earn credit for sharing with the public, the operator must maintain and provide the relevant source of information. Having provided the information to a third party who hosts and shares such information (e.g. listing a satellite’s mass on Wikipedia), would not be sufficient to earn credit under this category. While operators are encouraged to share information freely and easily with the public, requiring users to register and create an account and/or agree to terms of use would not prevent an applicant from receiving credit under this audience unless such terms of use provide for significant restrictions on use, as determined by the SSR issuer.

Weighting is determined by an analysis of the contribution to spaceflight safety, as well as current operator practices, and operator concerns about different forms of data sharing. Forms of data sharing with a more significant impact on space sustainability receive more points. In answering these questions, an SSR applicant should provide their best estimate for their intended capabilities and actions at the time of their submission - either for initial evaluation or re-evaluation.

Detailed information about the specific categories of activities within the Data Sharing Module:

1. Collision Avoidance Coordination Information

  • Information to be shared/credited: contact information for flight dynamics team or other appropriate technical/operational contact for collision risk mitigation (likely name(s), title(s), phone number(s), email address(s), list of controlled objects by NORAD CAT ID or International Designator, languages spoken), information about the time zone in which that individual or team operates, and response time guarantees as appropriate. An operator would also be asked to commit to publishing this information somewhere accessible and ensure it remains up to date to receive credit.
  • Relevance: Currently, many, if not most, high-risk conjunctions involving active satellites controlled by different operators are resolved via manual communication between the involved operators. There is an operational need to be able to reliably reach the contact associated with a given object to ensure the operator is aware of the conjunction and so any necessary collision avoidance manoeuvres can be planned and coordinated.Importance: Basic contact information is considered highly important. Hours of operation and response time guarantees are important, but secondary to timely and accurate contact information.

2. Satellite and Mission Information

  • Information to be shared/credited: Information relevant for operators attempting to identify, assess and avoid high- risk conjunctions. This includes launch vehicle timing and trajectories, both planned and actual, if satellites have manoeuvre capabilities, operational vs. non-operational status, satellite ephemeris information (historical, and planned future ephemeris incorporating manoeuvres. This is evaluated based on planned behaviours in the baseline SSR and updated based on actual practice during the on-orbit phase), ephemeris covariance information and information about how that covariance information was generated.
  • Relevance: Launch information helps operators and SSA providers improve overall situational awareness, particularly as the number of launches and complexity of spacecraft deployment information continues to increase. Operational status information helps operators determine whether coordination is possible or necessary. Ephemeris information improves SSA, as operator orbit determination is often better than non-cooperative estimates. Covariance information helps determine if satellite position information is decision-quality or if more information is required.
  • Importance: Launch information is helpful, but less of a concern for most operators than on-orbit operations. Sharing information about operational status is important. Sharing current/predicted ephemeris and covariance information is highly important.

3. Satellite Characterization Information

  • Information to be shared/credited: Satellite mass and size (either dimensions of a bounding volume, simplified CAD models, or other approach). These data are unlikely to change significantly during the operational life of most satellites. An operator would also be asked to commit to publishing this information somewhere accessible and assure it remains up to date.
  • Relevance: Satellite mass and size will be provided to the SSR issuer and used as part of the footprint calculations, but will not necessarily be released publicly. Knowing accurate mass and size information for operational satellites can help increase the fidelity of orbit propagation and conjunction assessments by third parties.
  • Importance: This information is considered important for the above reasons.

4. Autonomous systems (Subset of Satellite Characterization Information)

  • Information to be shared/credited: As more satellites use autonomous collision avoidance algorithms, having public information about their concepts of operation will be important for these systems to be designed to avoid feedback loops between systems that lead to unsafe behaviour. Information could be shared about how these systems function at a high level, the decision timelines used, and how other operators should coordinate with the operator of spacecraft with autonomous manoeuvre systems mechanisms to avoid uncoordinated collision avoidance manoeuvres. Specific items to be shared would include the criteria for when a manoeuvre is triggered, where and with what frequency planned autonomous manoeuvres are reflected in shared SSA information, and emergency stop procedures to interrupt autonomous procedures in case of malfunction.

Relevance: This is highly important in certain orbital regimes and will grow more important as such systems become more widespread.

  • Importance: This is listed as somewhat important, as it helps other operators in overlapping orbits coordinate to avoid hazardous conjunctions and unintended anomalies when operators’ satellites react to one another’s autonomous manoeuvres.

This category is only scored for operators who intend to operate or operate autonomous satellite manoeuvre systems (defined as systems that execute satellite manoeuvres without explicit manoeuvre approval by a human prior to execution). In that regard, operators with no such systems will not be penalized when the module score will be aggregated.

5. Other forms of data sharing (BONUS)

  • Information: radio-frequency information, spacecraft anomaly information, and datasets to support academic and governmental research
  • Relevance: other forms of data sharing also support space sustainability, but in ways more removed from operational physical collision avoidance. This category provides an opportunity for operators to get additional bonus credit for their contributions to sharing this data.  It is expected that data shared will vary based on the operator and operational needs. Accordingly, this category is deliberately less defined. It is anticipated that for much of this data sharing, operators will share different information with different audiences. Nevertheless, such data sharing should be substantive and in sufficient detail to provide a clear and articulable benefit to at least one external stakeholder in the relevant category.
  • Information: Documented and available application programming interfaces or other machine to machine interfaces.
  • Relevance: Well documented and available machine to machine interfaces provide ways for other providers to automate and make use of provided data in operational processes and provide additional reliability and greater ease of use as compared to scraping techniques. Operators could receive additional points if they make all data in a category (Collision Avoidance Coordination Information, Satellite Metric Information, Characterization Information) available in a documented API or other technical interface suitable for automated use.

Scoring Guidance: Operators can receive credit for any of the activities they do in any category of data sharing. The activities are listed with scores showing the points they receive for sharing a particular form of information with a particular audience. The operator can earn points for all the actions they take, including sharing a single kind of information with multiple audiences. During the scoring process, the total number of points earned by the operator are divided by the total potential points. The normalised point total is an input to the full SSR calculation.

Collision Avoidance Coordination Information
Publish + update collision avoidance contacts information:

• name(s)
• title(s),
• phone number(s),
• email address(s),
• list of controlled objects by NORAD ID or International Designator
• languages spoken)

0 10 10 12 12
Publish + update collision avoidance contacts time zone/hours of operation 0 3 3 3 4
Publish + update COLA contact/coordination response time commitments 0 1 2 2 1
Satellite and Mission Information
Publish + update satellite ephemeris (including manoeuvres, for LEO: 7 days, MEO/GEO: 14 days into the future). Sharing archived data is encouraged, but not required 0 12 8 15 15
Publish + update covariance information 0 6 5 5 6
Publish + update covariance characterization/validation 0 1 2 3 3
Publish + update launch vehicle timing/trajectories (planned and actual) 0 3 1 1 2
Satellite Characterization Information
Publish + update satellite mass 0 4 3 4 4
Publish + update satellite manoeuvrability (manoeuvrable/non-manoeuvrable) 0 5 5 6 6
Publish + update satellite manoeuvrability capability [*] 0 5 5 6 6
Publish + update satellite operational status (operational/non-operational) [*] 0 5 5 6 6

If the satellite uses autonomous systems (systems without a human in the loop) for satellite manoeuvring, publish + update:

● The criteria for when a manoeuvre is triggered

0 5 3 5 5

● Where and with what frequency planned autonomous manoeuvres are reflected in shared SSA information

0 5 3 5 5

● If emergency stop procedures exist to interrupt autonomous procedures in case of malfunction and how another operator should request an emergency stop

0 2 2 3 3
Other forms of data sharing (BONUS)
Radio-frequency Information to support interference avoidance/mitigation/geolocation 0 1 4 3 3
Spacecraft anomaly information 0 1 2 3 4
Other datasets to support government/academic research [*] 0 3 3 3 4
APIs or other means for automatic machine to machine access to above information [*] 0 1 1 1 2