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Chapter 18 Vocab
Astronomy Voab
Term | Definition |
---|---|
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. |