SkyLabs and University of Maribor use ‘Black Sun effect’ for space navigation

Researchers from the University of Maribor and the company SkyLabs are utilizing the ‘Black Sun effect’ to advance autonomous space navigation. The phenomenon, which appears as a black dot in the center of the Sun in images, is not a camera malfunction but a characteristic behavior of certain CMOS image sensors under extreme lighting conditions.

Dr. Iztok Kramberger, project leader for TRISAT and innovation director at SkyLabs, explained that the team is intentionally using this effect as a visual reference. By combining the ‘Black Sun’ with observations of the Earth and Moon, a spacecraft can autonomously determine its orientation, position, and movement in space. This technology is a critical step toward achieving fully autonomous navigation far beyond Earth.

The TRISAT-S nanosatellite, which carries six miniature cameras, was launched into Low Earth Orbit (LEO) on September 5, 2026, via an Isar Aerospace Spectrum rocket. The European Space Agency (ESA) recently recognized this achievement by selecting the image as its ‘Technology Image of the Week’ for the third time.