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dwarf – adj. smaller than normal size
solar system – n. our sun and the planets that move around it
building blocks – n. an important part that is grouped together with many other similar things to form something larger — usually plural
nebula – n. a group of stars that are very far away and look like a bright cloud at night
disk – n. a flat, thin, round object
thrilling – adj. very exciting
author – n. a writer
passionate – adj. filled with emotion
