# Ajisai 3D model

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

Free 3D model of Ajisai, a satellite, built from published dimensions by Space Radar. 12,358 triangles, 92 kB glTF, MIT.

- **Class:** Satellites
- **Mission:** Technology and science
- **Triangles:** 12,358
- **File:** ajisai.glb, 92 kB, glTF 2.0 binary (meshopt)
- **Look:** Flat colours
- **Size:** 2.1 m across
- **Made:** Built from dimensions
- **Added:** 2026-10-13
- **NORAD:** 16908
- **Download:** https://raw.githubusercontent.com/Sara-Managed-Projects/space-radar/main/site/models/ajisai.glb
- **Mirror:** https://git.sara-agent.org/sara-projects/space-radar/raw/branch/main/site/models/ajisai.glb
- **Viewer:** https://www.spaceradar.ai/model/?id=ajisai
- **On the live map:** https://www.spaceradar.ai/#at=sat-16908
- **Licence:** MIT (https://github.com/Sara-Managed-Projects/space-radar/blob/main/LICENSE)
- **Credit:** Ajisai 3D model by Space Radar (spaceradar.ai), MIT License

Canonical: https://models.spaceradar.ai/ajisai/

## 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 the published counts of Ajisai's mirrors and retroreflectors.

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

## Dimensions

- Diameter: 2.15 m
- Mirror max side: 0.25 m

Source: eoPortal, https://www.eoportal.org/satellite-missions/egs, opened 2026-10-13: 'EGS is a passive spherical satellite of 2.15 m diameter and a mass of 685.2 kg, carrying 318 mirrors and 120 laser retroreflector assemblies (1436 corner cube reflectors)'. Kucharski et al., https://ilrs.gsfc.nasa.gov/lw15/docs/papers/Determination%20of%20AJISAI%20Spin%20Parameters%20using%20Graz%20kHz%20SLR%20Data.pdf, opened 2026-10-13: 'The LRR panels are almost uniformly distributed over the surface, arranged in 15 latitudinal rings [2]. There are 5 rings with 12 LRR's, 4 rings with 9 LRR's, 2 rings with 6 LRR's, and 4 rings with 3 LRR's each.' Kucharski et al. 2015 (Earth, Planets and Space, through https://web.archive.org/web/20230204033126/https://earth-planets-space.springeropen.com/articles/10.1186/s40623-015-0204-4), opened 2026-10-13: 'Each panel contains 12 CCRs except for the one mounted on the central ring - with 8 CCRs only.' Korobeynikova et al. 2012, https://oap.onu.edu.ua/article/download/83378/78950, opened 2026-10-13: '318 quasi-flat mirrors (spherical in fact - the radius of curvature of the mirrors is 8.4-8.7 m, and the size <= 0.25 m)' and 'In the literature we have not found information on the actual placement of the whole set of mirrors.' https://arxiv.org/html/2511.16780v1, opened 2026-10-13: 'a surface area of up to 393 cm2 each'. NOT CITED, AND OURS: which ring has how many panels, each ring's latitude, how many mirrors stand in each ring, each mirror's size, the cubes' 36 mm faces

## References

- [Ajisai (EGS), the ILRS mission page](https://ilrs.gsfc.nasa.gov/missions/satellite_missions/current_missions/ajis_general.html), JAXA, through the International Laser Ranging Service (NOT FREE: the page credits its photographs 'Courtesy of JAXA'. The copy on Wikimedia Commons ('Ajisai Satellite.jpg') is tagged public domain as a NASA work, which this credit contradicts, so it is not relied on)