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emit – v. to send (light, energy, etc.) out from a source
linear – adj. forming a straight line
solar system – n. our sun and the planets that move around it
minuscule – adj. very small
Goldilocks zone – n. a place in outer space that is not too hot, or too cold and could hold life
exoplanet – n. a planet outside our solar system
radius – n. a measure, taken from a straight line from the center of a circle or sphere to a point on the outer edge
