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Chapter 18 Vocab

Astronomy Voab

Astronomy The 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 it's axis.
Telescope An instrument that collects electromagnetic radiation form 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 A telescope that uses a curved mirror to gather and focus light from distant objects.
Electromagnetic Spectrum All of the frequencies or wavelengths of electromagnetic radiation.
Constellation A region of the sky that contains a recognizable star pattern and that is used to describe the location of objects in space.
Zenith The point in the sky directly above an observer on earth.
Altitude The angle between an object in the sky and the horizon
Horizon The line where the sky and the earth appear to meet.
Light-Year The distance that light travels in one year; about 9.46 trillion kilometers.
Created by: bluefish03