The International Space Station (ISS) is the largest human-made object in Earth orbit, making it an especially attractive target for ground-based resolved imaging.
The image of the ISS was captured on 10 July 2025 at the Swiss Optical Ground Station and Geodynamics Observatory Zimmerwald (SwissOGS) using ZimMAIN - our ASA AZ800,
an 80 cm aperture telescope with a 5.6 m focal length - and a ZWO ASI 585MC Pro camera.
Ground-based images suffer from atmospheric turbulence that blurs each image differently.
Here, we applied image reconstruction techniques from solar physics (Wöger 2007) to "remove" the atmospheric turbulence and create a very sharp image.
Two docked spacecraft are clearly visible:
- Progress 91 is docked to the aft port of the Zvezda Service Module.
- Crew-10 Dragon (Endurance) is docked to the forward port of the Harmony module.
Thanks to recent improvements in the tracking performance of ZimMAIN, we are now able to successfully track high-elevation passes of low Earth orbit (LEO) satellites.
