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glow – n. a soft, warm light
geology – n. the study of rocks and soil and the physical structure of the Earth
aurora – n. streamers or arches of light appearing in the upper atmosphere of a planet's magnetic polar regions caused emission of light from atoms
emission – n. the act of sending gas, heat or light out into the air
scan – n. the act of scanning, or looking at all part of something
altitude – n. the height of something above sea level
photochemistry – n. a part of chemistry that deals with the chemical effects of light
mission – n. an important task, usually involving travel somewhere
