Star trackers are optical sensors used on satellites to precisely determine and maintain their attitude or orientation in space. These advanced devices play a pivotal role in ensuring that satellites remain precisely pointed in the desired direction, a critical aspect of their operational success.
Using a state-of-the-art star catalogue as a reference, star trackers capture high-resolution images of celestial bodies, particularly stars, present in the satellite’s field of view. These images are then compared to the known positions and brightness of stars stored in the star catalogue. By accurately identifying the stars and measuring their angles relative to the satellite’s reference frame, star trackers calculate the satellite’s precise attitude in three-dimensional space.
The star catalogue used by these trackers typically contains a vast number of stars with precisely known positions, and it may also include other celestial objects, such as planets and galaxies, for further accuracy. The use of star trackers ensures that the satellite maintains a stable and accurate orientation, which is crucial for various satellite missions, including Earth observation, remote sensing, communication, and scientific research.