Blink comparator

A blink comparator is used in astronomy to the comparison of two photographic plates on which to make visible celestial objects that have changed in the past between recorded time. Unlike in stereocomparator the examining astronomers are made visible in the blink comparator to compare the two shots in rapid succession at a time ( similar to a flipbook ). Thus, asteroids and comets are identified by a jumping back and forth due to your movement among the stars, and the light change of variable stars is shown by a pulsation caused by the different images of the bright star on the two shots. Many such objects have been discovered since the introduction of astrophotography in this way.

Thus succeeded in 1930 Clyde Tombaugh when comparing two photographic plates, the discovery of the dwarf planet Pluto.

Due to the increasing use of electronic detectors ( such as CCD ) and the appropriate software for the automatic comparison of images of the sky and for the detection of variable stars, asteroids and other objects has largely lost its importance in the modern astronomy the blink comparator.