stjernesensorer

Stjernesensorer, in Norwegian, translates to star sensors. These are optical sensors used in spacecraft navigation. Their primary function is to determine the precise orientation and attitude of a spacecraft by observing the positions of stars. A star sensor typically contains a lens, an image sensor (like a CCD or CMOS), and processing electronics.

When a star sensor looks at the sky, it captures an image containing many stars. Sophisticated algorithms then identify these stars by comparing their observed positions and brightness to an onboard star catalog. By recognizing at least a few stars, the sensor can accurately calculate its own position and the spacecraft's orientation in three-dimensional space. This is crucial for maintaining a stable platform for scientific instruments, pointing antennas towards Earth, and executing orbital maneuvers.

Star sensors offer high accuracy and are not dependent on external signals like GPS, making them reliable for deep space missions where GPS is unavailable. They are a fundamental component of modern spacecraft attitude determination and control systems. Unlike gyroscopes, which can drift over time, star sensors provide an absolute reference frame based on the fixed positions of stars, allowing for periodic recalibration and correction of accumulated errors. This makes them essential for long-duration missions requiring precise pointing.