Aristarchus of Samos (circa 310-230 BC), Greek astronomer and mathematician

Aristarchus (crater), a prominent lunar impact crater

Aristarchus, sive De contemptu linguae Teutonicae, the first essay of German poet Martin Opitz von Boberfeld

Aristarchus of Thessalonica (1st century), Eastern Orthodox saint

Aristarchus of Samothrace (circa 220-143 BC), Greek grammarian

3999 Aristarchus, a small main belt asteroid

Aristarchus of Tegea (5th century BC), Greek writer

Aristarchos 2.3 m Telescope Project, a telescope project