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asteroid – n. any one of thousands of small planets that circle around the sun
solar system – n. a star other than our sun and the planets that move around it
swirl(ing) – v. to move in circles or to cause something to move in circles
alien – adj. from somewhere other than the planet Earth
interact(ed) – v. to come together and have an effect on each other
fit(ting) – v. to be the right size and shape for someone or something
cluster – n. a group of things or people that are close together
proximity – n. the state of being near
comet(s) – n. an object in outer space that develops a long, bright tail when it passes near the sun
collide(d) – v. to hit something or each other with strong force
