astrocompass

The astrocompass works by observing the direction of stars and other celestial bodies.

Polar exploration was one of the fields in which the astrocompass saw the most use, for the reasons described above.

He told the pilot to keep an eye on the astrocompass, then took the elevator down to the reactor chamber.

The astrocompass system was deleted.

An astrocompass is a navigational tool for determining the direction of true north through the positions of various astronomical bodies.

Because of this procedure, an astrocompass requires its user to be in possession of a nautical almanac or similar astronomical tables, one of its chief disadvantages.

Before the advent of electronic navigational aids such as GPS the most reliable way to ascertain north in such circumstances was through the use of an astrocompass.

In its most basic form, the astrocompass consists of a base plate marked with the points of the compass, with a mechanism known as an equatorial drum mounted on it.

Once all these settings have been made, the astrocompass is simply turned until the astronomical body is visible in the sights: it will then be precisely aligned to the points of the compass.

The Litton AN/ASQ-119 Astrotracker is an astrocompass used for navigational purposes as part of the avionics suite mounted on FB-111A Aardvark aircraft.

Thus, with knowledge of the current time and geographical position in the form of latitude and longitude, which are set on the instrument using dials, an astrocompass can be sighted on to any astronomical object with a known position to give an extremely accurate reading.

GPS and other similar forms of electronic navigation aids mean that the astrocompass is now functionally obsolete anywhere except for areas very close to the poles where GPS coverage is not available and there are no current electronic navigation aids.