#star tracker

• Astrocompass — A high-precision optical or gyroscopic navigation instrument used to determine the direction of travel (heading) and azimuth of a vehicle (ship, aircraft, or spacecraft) by directly observing and automatically tracking the position of known celestial bodies (such as the Sun, Moon, or specific stars). This device is essential in polar regions or space, where classic magnetic compasses become completely ineffective due to Earth's magnetic anomalies or the lack of a reference magnetic field.
• Astrocompass — The modern synonymous variant of the term astrocompass; a mechanical, optical, or electronic instrument used to determine true north, a vehicle's heading, and azimuth by directly sighting and tracking celestial bodies. This device plays a crucial role in high-altitude, high-precision aerial or maritime navigation, functioning as an independent redundant system in the event of magnetic or electronic GPS equipment failure.
• Astronavigation — The science, technique, or method of guiding and determining the position, trajectory, and speed of a vehicle (maritime ship, aircraft, or spacecraft) through astronomical observations performed on celestial bodies (Sun, Moon, stars, or reference planets). In the context of modern spaceflight, it represents an essential pillar of astrodynamics, utilizing stable optical sensors (star trackers) for the autonomous orientation of interplanetary probes when ground guidance signals are unavailable.