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Chapter 18 Vocab

Astronomy The scientific study of the universe.
Year The time required for the Earth to orbit once around the sun.
Month A division of the year that is based on the orbit of the moon around the Earth.
Day The time required for Earth to rotate once on its axis.
Telescope An instrument that collects electromagnetic radiation from the sky and concentrates it for better observation.
Refracting Telescope A telescope that uses a set of lenses to gather and focus light from distant objects.
Reflecting Telescope
Created by: mesquared