EntityQ884408· pop 23· linked from 37 articlesblink comparatorSign in to saveAstronomical instrument used to measure movements or variations in the brightness of celestial objectsConnectionsSolar SystemEntityPlutoEntitycometEntityasteroidEntityWayback MachineEntityastronomerEntitybinary starEntityClyde TombaughEntityvariable starEntitybibcodeEntityproper motionEntityvisual systemEntityastrophotographyEntityamateur astronomyEntitycharge-coupled deviceEntityLowell ObservatoryEntityCarl Zeiss AGEntityslide projectorEntityphotographic plateEntitydouble starEntityCategories1904 in scienceAstronomical imagingObservational astronomyOptical devicesProducts introduced in 1904Zeiss (company)