Methodology

What the ISN Orbital Index Is

A structured reporting layer that combines orbital object inventory, change-event tracking, and long-term infrastructure indicators to support journalism, analysis, and public accountability.

Data Sources

• Cataloged object and satellite records (as available in ISN source pipelines)
• Change-event records for new objects, decays, and notable orbital movement
• Latest orbit parameter snapshots where available (for reporting context)

Public-facing sourcing principles: Trusted Sources

Update Cadence

The Index updates on a rolling basis as ingest completes. Page-level “Last updated” timestamps indicate the freshest available record for each view.

What Qualifies as a “Change”

• A newly cataloged object appears in tracked data
• An object is marked or inferred as decayed/reentered
• Orbit parameters move materially outside routine drift and are flagged as notable

Important Limitations

• Coverage depends on source availability, cadence, and schema completeness
• Not all operators or objects may include clean attribution fields
• Event classification can evolve as additional observations arrive
• Historical backfill depth may vary across object populations