Scientists Say

A weekly word defined, in a sentence and in context.

  1. Physics

    Scientists Say: Momentum

    This word describes a property of a moving object based on its mass and the direction and speed of its motion.

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  2. Space

    Scientists Say: Quasar

    This word describes the bright-shining core of a galaxy in which a supermassive black hole sucks in matter and releases a huge amount of energy.

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  3. Microbes

    Scientists Say: Amoeba

    Amoebas are single-celled microbes that move and eat with shape-shifting bulges that extend from their cells. Some are blobs. Others build a shell.

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  4. Earth

    Scientists Say: Jurassic

    During this time from about 200 million to 145 million years ago, dinosaurs reigned and many animals evolved, including birds and some early mammals.

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  5. Animals

    Scientists Say: Echolocation

    This word describes a method that some animals use to sense their environments by making sounds and listening for their echoes.

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  6. Earth

    Scientists Say: Ring of Fire

    This horseshoe-shaped path on the fringes of the Pacific Ocean holds most of the world’s active volcanos and earthquake sites.

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  7. Physics

    Scientists Say: Photon

    This word describes light as a particle. A photon is the tiniest possible bit of electromagnetic radiation.

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  8. Life

    Scientists Say: Enzyme

    This word describes a molecule that speeds up chemical reactions in living things. Enzymes work by lowering the energy needed for a reaction to occur.

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  9. Brain

    Scientists Say: Brainwaves

    These patterns of electrical activity in the brain look like spikes or waves.

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  10. Earth

    Scientists Say: Meteorology

    This word describes the study of processes in the Earth’s atmosphere, including the weather.

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