4MOST is a wide-field, high-multiplex, fibre-fed spectrograph, which will be mounted on the ESO VISTA telescope. High- and low-redshift surveys, targeting stars, galaxies, and AGN, can be executed in parallel, populating all the available 2436 fibers. Here, we present the 4MOST calibration plan, concentrating on the unique features dictated by the design of the instrument. These include the night-time backillumination of the fibers for precise metrology, simultaneous calibrations by dedicated fibers, attached night-time flatfield and wavelength calibration via a laser driven light source with a Fabry Perot etalon (FPE) on a moving carriage, and the observations of benchmark, telluric, and radial velocity standards for the science cross-calibration between 4MOST and complementary surveys from other telescopes.
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