NASA Is Looking for 'Planetary Protection Officer'

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cape – n. a piece of clothing that does not have sleeves and that fits closely at the neck and hangs over the shoulders, arms, and back : a short cloak

contaminate – v. to make (something) dangerous, dirty, or impure by adding something harmful or undesirable to it

conceive – v. a group of animals or plants that are similar and can produce young animals or plants : a group of related animals or plants that is smaller than a genus

species – n. a group of animals or plants that are similar and can produce young animals or plants : a group of related animals or plants that is smaller than a genus

predator – n. an animal that lives by killing and eating other animals : an animal that preys on other animals