EntityQ1035674· pop 20· linked from 262 articlesTusi coupleSign in to savemathematical device in which a small circle rotates inside a larger circle twice the diameter of the smaller circleConnectionsastronomy in medieval IslamEntityMuḥammad ibn Ibrāhīm al-FazārīEntitymathematicsEntityMercuryEntityuniverseEntityNicolaus CopernicusEntitygravityEntitygalaxyEntityAvicennaEntityInternational Standard Book NumberEntityOmar KhayyámEntityMuḥammad ibn Musa al-KhwarizmiEntitycircleEntityPtolemyEntitycompassEntityIslamic calendarEntityAverroesEntityWayback MachineEntityastrophysicsEntitydiameterEntityCategories13th-century inventionsAstronomy in the medieval Islamic worldLinear motionRoulettes (curve)