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Home Academy Tracking & TLEs Data sources (Space-Track, CelesTrak)
LESSON 05 OF 6

Data sources (Space-Track, CelesTrak)

Beginner ~7 min Slide deck Free

Satellite tracking depends on data — and there's a layered ecosystem of sources ranging from military tracking networks to open-data community projects.

Satellite tracking depends on data — and there's a layered ecosystem of sources ranging from military tracking networks to open-data community projects. Understanding where Orbital Radar (and every other tracker) gets its data helps you understand what you're seeing and its limitations.

What this lesson covers

Space-Track.org: the primary source

Space-Track is the public interface to the US Space Force's catalogue. It's the most comprehensive freely available source of TLE data.

CelesTrak: the community mirror

CelesTrak, run by Dr. T.S. Kelso, provides supplemental TLE data and curated satellite lists. It's often the first place trackers go because access is easier.

What Orbital Radar uses

Orbital Radar aggregates data from multiple sources to provide the most complete picture possible.

Key facts

💡Space-Track TLEs are the backbone of nearly every satellite tracker in existence, including Orbital Radar.
Tracking data flows from military sensors → Space-Track → CelesTrak → trackers like Orbital Radar.

Understanding this chain explains why data has latency, why some objects have stale TLEs, and why there's a gap between what military operators know and what public trackers can show.

All lessons in Tracking & TLEs
01What a TLE really is~8 min02Epochs, drag & decay~7 min03Propagation vs "accuracy"~8 min04The NORAD catalog (who assigns IDs)~7 min05Data sources (Space-Track, CelesTrak)~7 min06Reading a TLE line by line~8 min
← The NORAD catalog (who assigns IDs)All 6 LessonsReading a TLE line by line →
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