Time registration

In visual astrometry and geodesy, time registration refers to the determination and storage of precise points in time that occur when measuring star passages through the field of view of telescopes. The same expression is also used for newer, partially automated measuring methods, for example with prism astrolabes , zenith cameras or at the circumzenital .

In the case of visual observations, the registration takes place in at least 0.01 seconds, in photographic or electro-optical methods usually in milliseconds . In the past, writing or printing chronographs with wax or paper strips were used for registration, and digital stopwatches have been used increasingly since around 1980 , while direct registration in field-compatible computers predominates today.

In any case, the registration system must be connected to the international time system or that of the observatory . The former is usually done on a time signal transmitter , the latter often on special clock systems with quartz or atomic clocks, which in turn are synchronized with time signals.

See also

• Recording micrometer
• Timing
• Length determination

literature

• Karl Ramsayer : Geodetic Astronomy . Handbook of Surveying Volume IIa, § 12-14 (astronomical time systems) and § 37-49 (time services, time signals). JBMetzler, Stuttgart 1970
• Albert Schödlbauer : Geodetic Astronomy Basics and Concepts. de Gruyter, Berlin 2000, ISBN 3-11-015148-0