To determine position in space, an Apollo astronaut located a specific star using a telescope and then took a fix using a sextant.
Ed Collen, a NASA engineer, built this prototype device as a backup for Apollo astronauts in case their primary navigation system failed.
This is the master clock used at the Goldstone, California, Deep Space Network station from about 1983 to 2006.
Most inertial navigation devises use a gyro that measures motion by the change in vibration of a cup-shaped device.
Mariner 10 used the gravity of Venus to propel itself to Mercury.