Satellite catalog
The Load from Catalog button opens a curated, daily-refreshed set of real satellites sourced from Space-Track. Click ＋ beside any entry to add it to the scenario with SGP4 selected automatically — no TLE pasting required.
▶ Load the ISS from the catalog
What is in the catalog
The catalog is divided into two sections: Satellites (individual objects) and Groups (whole constellations). Use the Search box to filter both by name or slug.
Individual satellites
| Display name | NORAD ID | ?catalog= slug | Category |
|---|---|---|---|
| ISS (ZARYA) | 25544 | iss | Space station |
| Hubble (HST) | 20580 | hst | Science |
| Landsat 9 | 49260 | landsat-9 | Earth observation |
| GOES-16 (East) | 41866 | goes-east | Weather GEO |
| GPS III SV01 | 43873 | gps-iii | Navigation MEO |
| TDRS-10 | 27566 | tdrs | Relay GEO |
| Starlink (showcase) | — | starlink | LEO constellation (one representative) |
Constellation groups
| Display name | ?catalog= slug | Space-Track pattern | Cap |
|---|---|---|---|
| GPS Operational | gps-operational | NAVSTAR% | 31 |
| Starlink (sample) | starlink-sample | STARLINK% | 60 |
| Iridium NEXT | iridium-next | IRIDIUM% | 66 |
The caps in the table above reflect the pipeline’s per-group fetch limit, not the per-plan display cap. See free vs Pro group size below.
Epoch-age chip and stale badge
Every catalog entry shows a TLE epoch-age chip beside the name (e.g. “1.3 d”) indicating how many days old the element set is. When the epoch is more than 7 days old, the chip shows stale in red.
Why 7 days? SGP4 accuracy degrades as TLE age increases from the near-epoch baseline of roughly 1–3 km. A 7-day cutoff is a practical flag that the elements may need a refresh before time-sensitive work. The catalog is refreshed daily from Space-Track, so stale entries usually update within 24 hours.
A stale entry still loads and propagates — the chip is a warning, not a block. For pass prediction or conjunction screening, prefer entries with an epoch age of a day or less.
How loading works
Singles: click ＋ to add the satellite immediately. A brief “Added <name>.” toast confirms the add. The object card appears in Scenario Objects with the SGP4 propagator badge.
Groups: click ＋ to batch-load the group. Members are added in batches of 10 to keep the UI responsive; a toast confirms once all are loaded. If the group exceeds your plan’s cap, it is silently truncated to the cap size and an upsell prompt appears. All catalog objects use SGP4.
Free vs Pro group size
Loading a group on the free plan adds at most 12 objects; with ExoAtlas Pro the limit is 200. This is the client-side cap from LIMITS.groupObjects; the full pipeline cap for each group is higher.
?catalog= deep links
You can link directly to any catalog entry using the ?catalog= URL parameter. The slug is matched against singles first, then groups:
/orbit-visualizer/?catalog=iss— loads ISS (ZARYA) with SGP4./orbit-visualizer/?catalog=gps-operational— loads the GPS Operational group (capped at plan limit)./orbit-visualizer/?catalog=starlink-sample— loads the Starlink sample group.
See the URL API for the full parameter reference.
Caching and refresh
The catalog is fetched from data.exoatlas.com/featured-tles.json with ETag-based conditional requests. If your browser has a cached copy and the ETag hasn’t changed, the local copy is used. This means a just-refreshed catalog may not be visible until the ETag changes (usually within a few seconds of the pipeline run). If you need to force a fresh fetch, reload the page with the browser cache cleared.
Related
Can I add my own satellites beyond what is in the catalog?
Yes — click Add Object in the Scenario Objects section and select Two Line Element Set (TLE) as the input type. Paste any TLE (e.g. from Space-Track or CelesTrak), give it a name, and click Add Object. The catalog is a convenience; the TLE input has no cap.
Why does the Starlink showcase entry have no NORAD ID in the table?
The showcase satellite is dynamically picked from the Starlink group at pipeline run time — it is whichever Starlink satellite happens to be the first member of the group in that day’s data. The displayed name and TLE reflect the chosen satellite; it will vary day to day. For a stable individual reference, use one of the named singles.