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jet stream – n. a strong current of fast winds high above the Earth's surface
solar system - n. our sun and the planets that move around it
giant – n. a thing that is very large, powerful,
ionize – v. to make an atom or group of atoms that has a positive or negative electric charge from losing or gaining one or more electrons
symmetry – n. the quality of something that has two sides or halves that are the same or very close in size, shape, and position
hemisphere – n. half of the Earth
equator – n. an imaginary circle around the middle of the Earth
