# ERS-1 3D model

> Shape built from published dimensions and pictures; details simplified.

Free 3D model of ERS-1, a satellite, built from published dimensions by Space Radar. 6,812 triangles, 44 kB glTF, MIT.

- **Class:** Satellites
- **Mission:** Earth observation
- **Triangles:** 6,812
- **File:** ers-1.glb, 44 kB, glTF 2.0 binary (meshopt)
- **Look:** Flat colours
- **Size:** 12 m across
- **Made:** Built from dimensions
- **Added:** 2026-10-14
- **NORAD:** 21574
- **Download:** https://raw.githubusercontent.com/Sara-Managed-Projects/space-radar/main/site/models/ers-1.glb
- **Mirror:** https://git.sara-agent.org/sara-projects/space-radar/raw/branch/main/site/models/ers-1.glb
- **Viewer:** https://www.spaceradar.ai/model/?id=ers-1
- **On the live map:** https://www.spaceradar.ai/#at=sat-21574
- **Licence:** MIT (https://github.com/Sara-Managed-Projects/space-radar/blob/main/LICENSE)
- **Credit:** ERS-1 3D model by Space Radar (spaceradar.ai), MIT License

Canonical: https://models.spaceradar.ai/ers-1/

## How it was made

Built in code from published dimensions and photographs, with no image-to-3D generator and no one else’s mesh. 3D model: built by Space Radar from published dimensions and a photograph of the full-size model of ERS by abrev (public domain).

built by this project in code (the private tool model-from-images: assemble.py, from a yaml of primitives), from the cited dimensions and the pictures under `references`; no image-to-3D model was used, and no published mesh (NASA's 3D Resources on GitHub, 1 583 paths read 2026-10-13, has none of this craft; the survey of 2026-10-13 found no agency model of it under usable terms; ESA's own pictures and models were NOT used: ESA's terms forbid derivative works)

## Dimensions

- Overall height: 11.8 m
- Payload module height: 3 m
- Payload module side: 2 m
- Solar array long: 11.7 m
- Solar array wide: 2.4 m
- Sar antenna long: 10 m
- Sar antenna wide: 1 m
- Scatterometer fore aft: 3.6 m
- Scatterometer mid: 2.3 m
- Altimeter dish: 1.2 m

Source: eoPortal, https://www.eoportal.org/satellite-missions/ers-1, OPENED 2026-10-14: 'The platform is a SPOT program bus (SPOT MK1 bus), modified to meet the needs of the ERS missions.'; 'The payload support module has dimensions of 2 m x 2 m x 3 m (height).'; 'The solar array (11.7 m x 2.4 m in size) consists of two 5.8 m x 2.4 m panels and supports a peak payload power of 2600 W. The antenna is a slotted-waveguide array made of metallized CFRP (Carbon Fiber Reinforced Plastic).'; '2384 kg (at launch), overall height of 11.8 m'; AMI in imaging mode: 'antenna size =10 m x 1 m; look angle = 23º'; AMI in wind scatterometer mode: 'Use of three separate sideways-looking antennas (fore, mid and aft beams'; 'swath width = 500 km (same side as SAR imaging)'; 'antenna length = 2.3 m (mid), 3.6 m(fore), 3.6 m (aft)'; 'RA-1 is operating in Ku-band, consisting of a reflector, waveguide feed, tripod plus supporting structure, horn feed and the waveguide'; 'antenna diameter = 1.2 m'; 'The MWR instrument uses a 60 cm Cassegrain offset-fed antenna to view the Earth in nadir direction'; LRR: 'diameter: ≤ 20 cm'; 'The ERS-1 mission ended on March 10, 2000, due to a failure of the onboard attitude control system.' THE PAGE DISAGREES WITH ITSELF on the array: 'a dual-wing solar array subassembly' and 'Solar array subassembly (2 wings)' in one place, 'two 5.8 m x 2.4 m panels' in another; the photographs show ONE array of two panels across the end of an arm, which is what is built. READ OFF THE PHOTOGRAPHS: the radar antenna across the far end of the body; the scatterometer's two long antennas in a V beyond it and the short one between them; the dish on the Earth face; the array on an arm beyond the platform, its long side square to the body; a gold payload module and a silver platform. HOW THE 11.8 m IS READ (ours): from the tips of the scatterometer's antennas to the array's far edge, along the body; the model is 11.8 m that way. OURS: the platform as 2 x 2 x 2 m; the arm's 1.3 m; the V's 45 degrees and the antennas' tilt; ten tiles on the radar antenna; the radiometer's box; every place on the Earth face.

## References

- [Ers1mod](https://commons.wikimedia.org/wiki/File:Ers1mod.jpg), abrev (Wikimedia Commons) (Public domain (released by its author, the Commons user abrev: 'Model of European Remote Sensing Satellite (ERS) in original size'; the Commons API's LicenseShortName, read 2026-10-14))
- [Maquette-ERS-1](https://commons.wikimedia.org/wiki/File:Maquette-ERS-1.jpg), Pline (Wikimedia Commons) (CC BY-SA 3.0 (Pline, own work; read 2026-10-14): share-alike, LOOKED AT ONLY, never fetched by the tool and not on any sheet)
- [Ers-1](https://commons.wikimedia.org/wiki/File:Ers-1.gif), unknown (Wikimedia Commons names none) (Commons says 'Public domain' and names NO AUTHOR AND NO SOURCE (read 2026-10-14): not relied on as free, LOOKED AT ONLY, never fetched by the tool and not on any sheet)