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exposure – n. coming in contact with something
shield – n. an object used to protect something
crater – n. a large round hole in the ground made by the explosion of a bomb or by something falling from the sky
cosmic ray – n. high-energy particles that move through space at nearly the speed of light
detector – n. a device that helps notice something that is hidden or unclear
immense – adj. extremely good
interact – v. to communicate with or react to
