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ch. 18 sec 1-3 vocab
Astronomy
Term | Definition |
---|---|
Astronomy | The study of the universe |
Year | The time required for the earth to orbit the sun |
month | a division of the year that is based on the orbit of the moon around earth |
day | the time required for the earth to rotate once on its axis |
refracting telescopes | a telescope that uses a set of lenses to gather and focus light from distant objects |
telescope | an instrument that collects electromagnetic radiation from the sky and concentrates it for better observation |
reflecting telescope | a telescope that uses 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 point where the sky and the earth appear to meet |
light-year | the distance that light travels in one year; about 9.46 trillion kilometers |