978-1-4222-3418-1

Series Glossary of Key Terms i l

airlock a room on a space station from which astronauts can move from inside to outside the station and back ammonia a gas used in refrigeration; can be deadly if inhaled biochemist a scientist who studies the chemistry of living things carbon dioxide the type of gas that is in the air that we breathe out cosmonauts space travelers from the Soviet Union or Russia deforestation the destruction of forest or woodland extravehicular something that happens outside a vehicle, in this case a space station meteorology the study of weather physicist a scientist who studies physics, which examines how matter and energy move and relate pulsars a type of distant star that sends out radio waves vacuum the absence of air

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