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dark matter – n. material yet to be observed by astronomers, but something they think exists in the universe because of observed gravitational effects
antenna - n. a device for sending or receiving radio or television signals
deserve – v. to have earned because of something
wavelength – n. the distance from one wave of energy to another as it is traveling from point to point
ultraviolet – n. used to describe light that cannot be seen and that has shorter wavelengths than violet light
specific – adj. special; exactly stated
frequency – n. the number of waves of sound or energy that pass by a point every second
absolute zero – n. the temperature that is believed to be the lowest possible temperature
signature – n. an identifying mark or quality
