Abstract
A laboratory instrument was designed and constructed that allows testing, calibrating, and servicing astronomical instruments without the use of a telescope. The instrument has an optical system that produces an image similar to the star image produced by a telescope. The simulator covers the range of F/7.5 to F/30 focal ratios; this is the range of focal ratios of the telescopes in operation at the Observatorio Astronómico Nacional. The distance between the base plate and the image plane can vary from 250 mm to 370 mm and it is possible to move the image position in a field 5 mm in radius around the optic axis. Two types of light sources are available; a laser in the red λ = 632.8 nm and a miniature incandescent lamp (white light source). It is also possible to insert gelatin or interference filters in the collimated beam.
