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This method uses the Doppler effect to measure the velocity of a spacecraft by observing the frequency change of signals sent to and from the spacecraft to ground stations. It is a primary method of tracking deep-space missions.

An INS uses gyroscopes and accelerometers to calculate the position, orientation, and velocity of a spacecraft without the need for external references. It's used in space missions to maintain knowledge of the spacecraft's motion when out of range of ground stations.

Star trackers are optical devices that measure the positions of stars using photodetectors or cameras. This information is used to determine the spacecraft's orientation (attitude) in space, essential for correct solar panel and antenna alignment.

Radio navigation systems determine the spacecraft's position by measuring the time delay of radio signals exchanged between the spacecraft and Earth-based antennas. It's frequently used in conjunction with Doppler tracking for deep space navigation.

When in Earth orbit, spacecraft can use GPS signals to determine their position and speed. Similar to terrestrial GPS, but with hardened receivers to operate in the space environment, especially useful for Low Earth Orbit (LEO) satellites.

In this traditional navigation method, spacecraft use observations of celestial bodies (e.g., the Sun, Moon, planets) to determine their position in space. This method provided critical backups in early space missions and is still relevant for deep space navigation.

TRN systems use onboard cameras or sensors to compare observed terrain features against an onboard map, allowing for precise landings on other celestial bodies like Mars. It was famously used by the Mars Perseverance Rover in 2021.