Transit instrument

In astronomy, transit instruments are used for the precise observation of star positions. The instruments can be divided into three groups:

for observation of star transits in the exact direction of South or North:

which allow transit measurements in any direction

Depending on the type of instrument, the measurements are carried out

The accuracy reaches from 0.2" (theodolites, small astrolabes) to 0.01" (modern meridian circles, Danjon). Early instruments (like the mural quadrants of Tycho Brahe) had no telescope and were limited to about 0.01°.

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