from Life on Earth and Beyond

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• headings

• photographs

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scientists who study life in the universe

the smallest living things

a group of animals living in one place

devices that detect changes in light, moisture, or other physical conditions

• rovers

• radiation

• colony

• sensors

dangerous energy rays that cannot be seen

• rovers

• radiation

• colony

• sensors

vehicles used to explore a planet's suface

• rovers

• radiation

• colony

• sensors