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Upload your first satellite

Difficulty: Beginner. Time: about 10 minutes. Needs: a browser; guest mode works.

You will import one satellite from a two-line element set (TLE), verify it renders and propagates exactly like the operator fleet, and learn to judge ephemeris staleness, which is the number one reason uploaded satellites "misbehave".

1. Get a TLE​

A TLE is two fixed-width lines (optionally preceded by a name line) describing an orbit at a specific moment, its epoch. Grab a current one for any active satellite from your flight dynamics team or a public catalog. The fresher the epoch, the better the tutorial behaves; prefer one no more than a few days old.

2. Import it​

  1. Open the console and open the Assets panel from the left rail.
  2. Choose import and either drop a .tle/.txt file or paste the TLE text directly.
  3. Read the validation result before confirming. The parser checks line structure (line 1 starts with 1 , line 2 with 2 ), agreement of the NORAD id across lines, and the mod-10 checksum on each line. Checksum mismatches warn but do not block; structural problems reject the record with the offending text quoted.

Expected outcome: one record accepted, zero rejected, and your satellite appears on the globe immediately under the import group, with a provenance badge.

3. Inspect it​

Click the satellite. The entity card opens with the same structured detail a fleet satellite gets:

  • Overview: name, NORAD id, ephemeris source, epoch, and epoch age.
  • Orbit: altitude, apogee and perigee, inclination, period, RAAN, and the rest of the element set.
  • Current state: sunlit or in eclipse, sub-satellite point, upcoming events.

Fields the importer cannot source show an explicit dash; nothing is invented. Press play on the timeline: the satellite moves with the same SGP4-plus-interpolation pipeline as everything else on the globe.

Expected outcome: the epoch age on the card matches your TLE's freshness, and the ground track looks physically sensible for the inclination you imported.

4. Understand epoch validity​

Propagating a TLE far from its epoch degrades into fiction, so the console gates honesty into the pipeline: each satellite propagates within a validity window of about 14 days around its own epoch, anchored consistently into the simulation window, and catalog entries more than 90 days behind the newest epoch are treated as decayed and dropped rather than drawn in fictional positions.

Try it: scrub the timeline far from your TLE's epoch and watch how the console treats validity, then check the epoch age on the card. For analysis-grade work, use TLEs whose epochs are close to the window you are studying.

5. Re-import and observe dedupe​

Import the same TLE again. Instead of a duplicate, the existing asset updates in place, keeping its id, selection state, and visibility. This is by design: a weekly TLE drop refreshes your fleet rather than multiplying it. See Import TLEs at scale.

Troubleshooting
  • Record rejected: the quoted line tells you why; the usual causes are wrapped lines from copy-paste, a missing leading 1 /2 , or mismatched NORAD ids across the two lines.
  • Checksum warning: common with hand-edited TLEs; the warning names expected and found digits. Safe to proceed if you trust the source.
  • Satellite not visible on the globe: check the group's visibility toggle in the Assets panel, then check the epoch. A very old TLE outside its validity window is intentionally not drawn.
  • Satellite in a surprising place: check epoch age on the card first; stale elements, not the renderer, are almost always the cause.

Where next​